S 639 
.G41 
Copy 1 



■ 



METHODS 



OF 



Analysing Fertilizers 



1884. 

PUBLISHED BY THE 

National fertilizer association, 

Baltimore. 



METHODS 



OF 



ANALYSING FERTILIZERS 



GERMANY AND THE UNITED STATES, 



-AND EFFORTS MADE IN BOTH COUNTRIES FOR ARRIVING AT 



UNIFORM METHODS AND RELIABLE RESULTS, 



PRECEDED BY SOME DATA ON THE 



FERTILIZER INDUSTRY IN GERMANY. 



COMPILED AND TRANSLATED 

BY 

A. de GHEQUIER, 
Secretary. 



PUBLISHED BY THE 

NATIONAL FERTILIZER ASSOCIATION 
Baltimore, March, 1884. 






Pkess of 
GUGGENHEIMER & WEIL, 

BALTIMORE. 



PREFACE, 



The subject of analysis and of commercial valuations of fertilizers 
claimed the earnest attention of the Board of Directors from the 
very time of the formation of this association. The great discre- 
pancies between analyses of the same goods in different States, and 
the practice of assigning commercial valuations to fertilizers on the 
basis of these analyses, seemed to call for energetic efforts to bring 
about, in some way, greater uniformity as regards the former and a 
different modus operandi as regards the latter. 

With this object in view, the association endeavoured to obtain 
information on that subject from official sources in European coun- 
tries and it is gratifying to be able to state that very kind and 
very full replies to the numerous inquiries made by the Secretary 
have been received. These inquiries were extended over the num- 
ber of manufacturing establishments engaged in Germany in the 
production of artificial manures, their total production and consump- 
tion, the control exercised by the government and by the agricultu- 
ral experiment stations, finally the status of the analysis question. 
Dr. Gr. Krause, the proprietor and editor of the "Chemiker Zeitung," 
responded by forwarding an exhaustive paper, from which copious 
extracts are made in the following pages. The Minister of Agri- 
culture for the Kingdom of Prussia, to whom the communication 
addressed to the Minister of Agriculture of the German Empire 
had been referred, forwarded in a printed pamphlet, compiled by 
Privy Councellor Dr. H. Thiel, the work of the latter. Then several 
prominent chemists, who had been written to for full descriptions 
of the methods used by them in the analysis of fertilizers, 
obligingly complied with the requests made of them. From the 
material obtained from these threefold sources and from other 
official documents the following compilation has been prepared. 
The Board of Directors concluded to append to it a synopsis of 
what so far has been done in this country towards accomplishing 
uniformity of method of analysis, and submits the following pages as 
the result of the work. 



Baltimore, March 1884- 



The important part which the comparatively young 
fertilizer industry plays in the German Realm, becomes 
apparent when it is borne in mind that about four 
hundred (400) establishments are engaged in the manufac- 
ture of artificial manures within its borders. 

According to the official import lists, there were imported 1 
during the year 1882, 116,150 tons of guano, of which quan- 
tity about 52,544 tons consisted of Peruvian guano, while 
the balance of 63,606 tons were phosphate guanos. These 
figures represent approximatively an average for a term of 
9 years. Besides the above quantities there were imported — 

Mineral Phosphates 20,739 tons. 

Bone Meal (exclusive of export) -3 2 >354 " 

And used 

Phosphorites and Coprolites from German Mines. ..38,718 " 
German Bone Meal, &c 4M7 8 " 

Of this aggregate quantity, viz : 249,439 tons were manu- 
factured in German factories — 

38,713 tons Peruvian Guano, requiring 12,997 tons Sul. Ac. 
63,600 " Guano Phosphate, 1 J= o 

9,402 " Phos. ofvar. kinds, I |||2 159,278 " 
20,740 " Imp. Mineral Phos. .' |||-< 
73,832 " BoneMeal,boneblkj | 
38,713 " Nat. Phos. Rocks, @ 75$ 29,035 

245,000 " Raw Material, requiring 201,310 tons Sul. Ac. 

The quantity of Sulphuric Acid tallies with the fact that 
of the total productions of this article in 1882, after de- 



ducting export and adding on import, about 298,647 tons 
were consumed, of which fully Yi found employment in the 
manufacture of fertilizers. The quantity of raw material 
on the other hand, tallies with the estimated production of 
fertilizers as made by the Association of German Fertilizer 
Manufacturers. 

Under the supposition that the superphosphates contain 
on an average 15$ of soluble phosphoric acid valued at 9c. 
per pound or $24 per ton, 

The total production represents a value of. $9,246,300 

To this must be added 

About 121,671 tons Chili-Saltpetre 6,806,800 

44,244 " Sulph. Ammonia 3998,400 

58.070 " Peruvian Guano "1 

5,530 " Fish Guano. J 3' '7 

24,889 " Imported Bone-meal } 

55,305 " German do. J '^ ^'' 

Making a total of. $25,477,900 

This does not include blood and horn and hoof prepara- 
tions, &c, nor Potash-salts of which were consumed, 

29,865 tons Kainit by farmers $122,094 

22,122 " Chlorkalium by farmers 725,900 

2,765 " Kali-Magnesia 40,460 

11,061 " Salts of other kinds 36,220 



About 65,813 tons of the value of. $924,674 

How much all other classes are interested in and affected 
by the fertilizer industry appears best from the considera- 
tion that the freights on raw and manufactured manures 
and materials amount to about 2 million dollars ; that 2 /i 
of the products of Pyrites-mines are consumed by it; that 
bag factories depend upon it to the extent of bags for 
663,660 tons, representing nearly $600,000; that the iron 
and coal industry is constantly engaged in keeping factories 
supplied with machinery and coal, the farmers in raising 
food for nearly 20,000 laborers, the banking establishments 
in furnishing credit to the trade to the amount of 15 to 20 



"million dollars, finally the tax-departments in levying at 
least 1,000,000 dollars on real-estate, &c, depending .upon 
or belonging to this industry. 

In the quantity consumed there were contained about 
150,000,000 lbs. Phosphoric acid and 63,000,000 lbs. of 
Ammonia, which, calculating 20 pounds to the Morgen 
'(1 Morgen=li acre) would indicate that about 10 million 
acres have been supplied in 1882 with artificial manures. 
With the steady progress in the application of fertilizers, 
the German industry will before long be confronted by the 
task to supply fertilizers for about 58 million acres, which 
constitute the area of Germany under agricultural cultiva- 
tion, hence it will have to become twenty times larger than it 
is now. From this consideration results as it is stated the 
duty of the government to protect this industry and to pre- 
vent by a duty on imported, particularly English fertilizers, 
•a competition fatal to the prosperous expansion of the 
'German industry. It is a matter of national interest in the 
estimate of Germany to see this industry grow vigorously 
•and to encourage capital to make investments in it. 

The foregoing extracts and condensations from the report 
•of Dr. Krause do not claim to give absolutely correct statis- 
tical information, yet they possess enough intrinsic value to 
serve as a measure of the magnitude and importance of this 
industry in Germany. The following data have been com- 
piled here from tabulated statements which, in their origi- 
nal form would hardly have given a correct insight into the 
'commerce of Germany with other countries in articles de- 
fend ent upon the fertilizer industry. 

The imports during the year 1882 of natural guanos, 
-crude potash, nitrate of soda, sulphate of potash, muriate of 
potash, and other fertilizer materials amounted to 467,739 
tons, while the exports of the same articles for the same 
.year consisted in 326,039 tons. 

For the first 6 months of the year 1883 the respective 
-figures are: Imports, 214,631 tons; Exports, 139,428 tons. 

A communication, dated Berlin, October 4, 1883, from 
the ministry of Agriculture, Domaines and Forrests con- 



tains the following significant passages : " The manufacture- 
of artificial manures is perfectly free and in no way ham- 
pered by restrictions. About the mode of voluntary (not 
obligatory) control which the agricultural experiment sta- 
tions exercise over the fertilizer-trade, you will find full 
information in Dr. Thiel's work " 

Privy Councellor Dr. H. Thiel begins his pamphlet " on 
the consumption and control of artificial manures in Prus- 
sia" with an expression of regret that correct statistical 
information regarding consumption cannot be given. This 
alone, he says, would furnish a reliable gauge for measuring 
the intensity of the cultivation of the soil (high-farming), 
thus identifying agricultural progress with the development 
of the fertilizer industry. It would, moreover, he contends*, 
be the means of indicating to what extent care is bestowed 
upon the preservation of the fertility of the soil and enable 
us to draw valuable conclusions in regard to the elements- 
of plantfood required by the various crops and modes of 
cultivation. Last, but not least, he thinks that data of 
consumption would be the best argument against a saying 
which, strange to say, has not yet entirely lost currency > 
viz : that artificial manures on certain soils are inefficient 
and valueless. But, he adds, that only in districts which 
are very much behind the times in agricultural progress i& 
this absurd statement heard, since it is quite certain that the- 
farmer cannot attain the maximum yield from the soil- 
without providing by artificial means the indispensable plant 
nutriment. Apart from this consideration it is, he says, 
of great importance to know the manner in which the trade- 
in fertilizers is being done and the character and quality 
of these artificial manures. In this last respect Germany 
points with great and just pride to the development of this- 
industry. The numerous agricultural experiment stations- 
which originally were established for the investigation of 
purely scientific questions, rendered incalculable services to* 
agriculture by devoting themselves to the rather monotonous 
task of exercising a certain control over artificial manures. 
The old mode of selling fertilizers, called by a generic name^ 



9 

(brands), has been replaced by one where the analysis fur- 
nished with the goods determines their character, and even 
this mode is now already being superseded by a still more 
rational way. Farmers no longer buy so and so many bags. 
of guano or bonemeal, &c, but order from the manufac- 
turers so and so much of each desired plant-nutriment, viz :: 
phosphoric acid, ammonia and potash and the price of these 
ingredients is quoted to them. This stage of transition to- 
the most rational mode of dealing between farmer and 
manufacturer is now obtaining throughout Germany. Rep- 
resentatives of the fertilizer-industry endeavored at various 
times to have the government establish a compulsory con- 
trol of fertilizers and uniform regulations applicable to the 
whole trade, but this has been opposed by the Agricultural 
Experimental Stations and Agricultural Associations, as in- 
opportune and by no means required by the existing state 
of affairs. 

The following agricultural experiment stations, Inster- 
burg, Konigsberg, Danzig, Eldena, Regenwalde, Dahme, 
Posen, Breslau, Kiel, Halle a. S., Hildesheim, Gottingen, 
Munster, Bonn, Marburg and Wiesbaden exercise in the 
Kingdom of Prussia, a control, mutually agreed upon 
between each station and factory, over about 220 manu- 
facturing establishments. As regards the mode of control 
exercised by these agricultural experiment stations over 
the fertilizer-trade, Germany, as appears from the reports 
received, passed through the same stages through which 
Belgium passed and as the result was in both countries the 
same, it is well worth while to go more fully into the subject. 

In the first place the stations interfere in no way with the 
selling-prices, nor with the stipulations of the sale-contracts 
made by the manufacturers. 

In the second place the stations assume control over the 
products of such factories only, as voluntarily report them- 
selves, that is, desire to sell their goods subject to the control 
of the various agricultural experiment stations. In all such 
cases, namely, in cases where factories sell subject to the 
control of stations, these are notified of the sale-conditions- 



10 

^and as appears from numerous forms of contracts appended 
to Dr. Thiel's report, the stipulations are pretty uniform. 
The purchaser must draw a sample according to the mode 
prescribed in the contract in presence of one or two wit- 
nesses, divide this into 3 equal portions and forward it to 
the station. Tins must be done, however, inside of a fort- 
night after the receipt of the goods. The chemist of the 
station, or the chemist agreed upon in the sale-contract, 
then analyses the sample and a discrepancy of 5-10$ in 
phos. acid, 3-10$ in am., and 5-10 in potash is not consid- 
ered an evidence of shortage of valuable ingredients, be- 
cause the chemists concede that such differences, in spite of 
close observation of the same method of analysis, are una- 
voidable. Any greater shortage is allowed for at a certain 
price agreed upon between buyer and seller, an excess of 
one ingredient being considered an offset to a shortage in 
another. It is the manufacturer who in all cases deter- 
mines the value of phosphoric acid, ammonia and potash 
and not the station. 

As Dr. Thiel well remarks, the differences established 
now and then, are so small that the control in no way im- 
pedes the healthy development of the fertilizer industry 
-and the same deserves iu his opinion to be called as so 
honest and clear a trade that one would wish the same 
could be said of the trade in seeds and feeding articles. 
All this applies to the present state of affairs since December 
18th, 1881. 

Prior to that date there existed the same lack of uniform- 
ity in the results of analyses, which is the source of so just 
•complaints in this country. 

From letters received from Prof. Dr. Fresenius at Wies- 
baden ; Dr. Ulex, Hamburg ; Dr. Hugo Schulz, Magde- 
burg ; Dr. Saxhlot, Munich, and Prof. Kroker, Breslau, 
and from pamphlets published on the subject of analysis of 
fertilizers, it appears that several conventions of agricultural 
chemists, directors of experiment stations, and manufac- 
turers, were held before uniformity in the method of analy- 
sis was established. The first of these conventions was held 



11 

at Madgeburg in 1872, then followed those at Danzig and 
Munich, and, finally, on December 18th, the last one at 
Halle a. d. S., which resulted in the adoption of the follow- 
ing: 

METHOD OF ANALYSING EERTILIZEKS 

According to the agreement made by the Directors of Agricultural 
Experiment Stations, Chemists and Manufacturers in Con- 
vention assembled at Halle on December l§th, 1881. 

A— PREPARATION OF SAMPLES IN THE LABORATORY. 

1. Dry samples may be put through a sieve for the better 
breaking up of lumps, if this on account of a lumpy condi- 
tion appears desirable. But whatever remains on the sieve 
should be as thoroughly broken up as to pass finally through 
the sieve, and this portion should be thoroughly mixed with 
the portions that passed first through the sieve. 

2. "With moist samples the use of the sieve is impractica- 
ble ; the preparation of the sample is then confined to a 
thorough mixing in the mortar. 

3. The weight of samples should be determined on their 
arrival and the whole sample should be prepared and pre- 
served in glass jars with tightfitting stoppers, if possible in 
a cool place. 

4. When balances of samples are to be forwarded, either 
the whole balance should be sent to the controlling chemist 
•or a thorough mixing of the whole balance should take 
place before dividing it. 

In case of crude phosphates and of bone-black, the moist- 
ure should be determined for the purpose of identification 
at a temperature of 100°C with the former and 130°C with 
the latter. 

In case of fertilizers which during the process of drjing 
loose carbonate of ammonia, this should be determined. 

5. Chemists should endeavor to receive only carefully 
<drawn samples, packed in tight vessels and at least 500g 
weight. 



12 

B.— DETERMINATION OF SOLUBLE PHOSPHORIC ACID IN 
SUPERPHOSPHATES. 

I. Method op Extraction. 

1. 20g of the sample are treated with water in the mor- 
tar, slightly pressed with the pistill without finely tritu- 
rating and washed into an 1 litre-flask. 

2. After this operation the flask is at once to be filled up 
to the mark. 

3. All superphosphates have to be digested for 2 hours, 
at the temperature of the room under frequent shaking and 
then are filtered. 

4. The volume of the insoluble is diregarded. 

5. In case of superphosphates containing not much more- 
than 20$ of phos. acid, 200CC of the filtrate are mixed 
with 50CC of a solution of acetate of ammonia (:100g 
pure acetate of ammonia and 100CC of concentrated acetic 
acid to 1 litre:) for the purpose of separating the phosphates- 
of iron and alumina. The deposited precipitate is filtered^ 
washed 3 times with hot water, burnt out and weighed and 
calculated as consisting of h. of the weight of phosphoric 
acid. 

6. In case of superphosphates containing more than 
20$ of soluble phosphoric acid 100CC of the filtrate are 
diluted with 100CC of water after adding 50CC of the 
acetate of ammonia (as above described). 

II. Volumetric Determination of Phosphoric Acid. 

1. This process can be used with all superphosphates con- 
taining not more than 1% of phosphoric acid in combination* 
with iron or alumina. 

2. For the titration a solution of pure nitrate of uranium, 
has to be prepared. To obtain the normal concentration 
(:1CC=0.005 g phos. acid:) 1000 g of nitrate of uranium 
are dissolved in 28200CC of water and 100 g of acetate of 
ammonia solution added to neutralise the small quantities 
of free nitric acid generally present. 

3. The titre is determined either by the use of a solu- 
tion of the superphosphate, free of iron, containing about. 



13 

"16$ sal. phos. acid or by a solution of 7.5 g tricalcinm phos- 
phate in a corresponding quantity of sulphuric acid. — 
During the titration the same proportions of solution of 
phos. acid with acetate of ammonia are to be observed as in 
the case of superphosphates. 

In each case the percentage of phosphoric acid of the 
•control-liquid has to be determined by the molybdaen- 
method. 

4. In executing the analysis, 50CC of the nitrate from 
-the phosphate of iron are to be used and not to be diluted 
with washwater. The end of the reaction is determined 
-after strong boiling on a porcelain plate either by a finely 
powdered ferrocyanite of potassium or a freshly prepared 
solution of the same. 

-III. Execution of the Gravimetric Determination op Phos- 
phoric Acid by Moltbdaen. 

25 to 50CC of the phosphate solution containing from 
0.1 to 0.2 g phos. acid are emptied into a beaker and 
■mixed with enough concentrated solution of nitrate of 
•ammonia and enough molybdate-solution (:75 g of molyb- 
•date of ammonia dissolved in 500CC water at a tempera- 
ture of 50 to 60°C and 500CC nitric acid (1.2 specific gravi- 
ty) after shaking filled up to 1 litre:), so that the total 
liquid may contain 15$ nitrate of ammonia and that for 
-each 0.1 g phos. acid not less than 50CC of molybdate 
-solution be present. The contents of the beaker are heated 
in a waterbath to 80-90°C, put aside for one hour, filtered 
and the precipitate in the filter washed with a diluted solu- 
tion of nitrate of ammonia. The beaker is then placed 
under the funnel, the filter perforated by a platinum- wire, 
the precipitate washed with a 2£# ammonia liquid into the 
beaker, under stirring with a glass-stick, carefully washing 
■out the paper and as much 2£# ammonia liquid added to 
"bring the volume of the whole liquid to about 75 CO for 
»each 0.1 g phos. acid, 10CC of magnesia mixture are 
dropped in under constant stirring and it is then put aside 
Tfor 2 hours. The precipitate is then filtered, washed with 



14 

a 2£$ ammonia liquid until the chlorine reaction disap- 
pears and then dried. The precipitate with the filter is 
then put into a covered platinum-crucible, heated until the 
filter is carbonised, then burnt for 10 minutes with the 
crucible in an oblique position in the flame of a Bunsen 
burner, then heated with a blower until perfectly white,, 
placed in the exsiccator and cooled down and weighed. 

Concentration op Solutions. 

1. Molybdate solution, 150 g of molybdate of ammonia in. 
water to 1 litre, poured in 1 litre of nitric acid of 1.2 spec, 
gravity. 

2. Concentrated solution of Nitrate of Ammonia, 750 g- 
ammonitrat to 1 litre. 

3. Diluted solution for Washing Purposes, 150 g Am- 
monitrat and 10CC nitric acid to 1 litre. 

4. Magnesia Mixture, 55 g crystallised chloride of mag- 
nesium, 70 g chloride of ammonia in 1 litre of 2J$ ammonia 
liquid. 

C— DETERMINATION OF PHOSPHORIC ACID SOLUBLE 
IN CITRATE OF AMMONIA. 

5 g of the original superphosphate are treated under- 
pressure in a mortar by 100CC citrate of ammonia (citric 
acid dissolved in ammonia to neutral reaction, concentra- 
tion brought to 1.09 spec, gravity and then per litre 50CC 
ammonia liquid added), washed into i litre flask, digested 
one hour at 40°C, then filled up to the mark, filtered and 
the phos. acid determined in the filtrate, 60CC of magnesia, 
mixture having been added. 
There are now generally used 

Of precipitated phosphates, 1 g. 
" mineral superphosphates, 2 g. 
" mixed guanos, 5 g. 

D.— DETERMINATION OF INSOLUBLE PHOSPHORIC ACID. 

1. In JBonemeal. 5 g bonemeal are burnt, the ash dis- 
solved in hydro-chloric or nitric acid, the solution evapor- 
ated in a porcelain vessel in the waterbath, until all super- 



15 

fiuous acid is driven off, taken up with a few CC of acid' 
and filled up to 500CO. Of these 200CC are treated with 
50CC acetate of ammonia and titrated. 

The destruction of organic substances by chlorate of 
potassium and hydrochloric acid or nitric acid is admissible 
in place of burning. 

In case of bonemeal treated with sulphuric acid, this 
second process of oxydation has to be carried out under all 
circumstances. 

2. In Fish Guanos, Tankage and similar fertilizers. 
In these the destruction of organic matter has to be done not 
by burning but by oxydation by chlorate of potassium and 
hydrochloric acid or by fusing with soda and saltpetre or 
soda and chlorate of potassium. If the phos. acid is to be 
determined by molybdate then nitric acid has to be chosen 
for the oxydation to which in case of substances which it is. 
difficult to oxydise, 10CC of hydrochloric acid must be 
added. 

3. In Crude Phosphates. If organic substance is present,, 
it may be destroyed either by oxydation on the wet plan or 
by fusion as indicated above. In the latter case the silica 
has to be separated before the gravimetric determination of 
phos. acid, which is only necessary in exceptional cases if 
oxydised on the wet plan. Phos. acid is determined by 
molybdate." 

In the discussion prior to the adoption of the method for 
the determination of phos. acid soluble in citrate of ammo- 
nia (namely, reverted phos. acid) there was considerable dif- 
ference of opinion displayed. At first, Dr. M. Fleischer, of 
Bremen, to whom this subject had been referred for re- 
port, proposed that the Convention of Directors of Agricul- 
tural Experiment Stations and of chemists interested in the 
manufacture of artificial manures should declare 

1. That the method elaborated by Fresenius, Neubauer 
and Luck for the determination of so-called reverted phos- 
phoric acid by means of citrate of ammonia in its original, 



16 

tfbrin as well as in the form given it by Petermann and the 
^use of these methods for determining the value of phos- 
phates not soluble in water, does not afford any precise 
f ( reliable) analytical results. 

2. The figures obtained by that method do not afford 
any measure for determining the agricultural value of such 
phosphates. 

Discussing the first point Messrs. Prof. Maerker, Tollens, 
Kiihn, "Wagner, Henneberg, Albert, Brunner, von Grote, 
Pieper, Schroof and Stelling expressed opinions to the same 
•effect as the reporting Dr. Fleischer. The latter demon- 
strated by analyses the unreliability of these methods and 
laid stress upon the fact that temperature, proportion of 
•solution to quantity of sample, time of digestion, condition 
of the citrate solution according to the mode of its prepara- 
tion, the presence of other substances, the degree of pulveri- 
sation, &c.j materially influence the results, so much so that 
they make these methods absolutely impracticable. This 
applies as well to the determination of phosphoric acid in 
precipitated phosphates as also to the determination of 
so-called reverted phosphoric acid in superphosphates. He 
refers to the data on that subject laid before the convention 
at Munich and gives the results of experiments made by 
himself and others since then which corroborate the former. 
He emphasises particularly how the more or less breaking 
up of the sample influences very materially the results. 

Professor Tollens advocates oxalate of ammonium, be- 
cause, as he demonstrated, out of a sample of bonemeal of 
well-known established value, containing about 15$ phos. 
acid, he could not obtain more than 1$ by a diluted citrate 
of ammonia solution, nor even more by a concentrated solu- 
tion. The debate closed by the unanimous adoption of the 
following resolution, offered by Dr. Kiihn : 

"Notwithstanding the fact that the methods proposed 
and used for the determination of phos. acid soluble in 
citrate of ammonia are far from fulfilling their purpose, it 
is agreed that in case such determinations are asked for, the 



17 

method described in §C* be used, but that in each case 
attention be called to the deficiency of this method." 

From this action it is evident that the German chemists 
did not feel themselves authorized to let the value of a fer- 
tilizer depend upon an analysis not absolutely reliable. Yet 
it is quite certain that this method in the estimate of the 
chemists attending the convention was the best they were 
aware of and in spite of this being the case, they acknow- 
ledged that even that best method gave results so much at 
variance, as not to be relied upon and hence they shrunk 
from inflicting upon the trade, what they admitted would 
be a great injustice. In Belgium, where there are four expe- 
riment stations at Gembloux, Gand, Hasselt and Liege, as 
appears from a report of Mr. Petermann, the director of the 
station at Gembloux, there has also been held a meeting of 
the several chemists during the year 1880 in order to insure 
uniformity of operations by agreeing upon one analytical 
method to be adopted by all. The result of this con- 
vention was at once communicated to the manufacturers 
of fertilizers in order to enable them to have the mate- 
rials used in the manufacture of manures analysed by the 
same process so as to ascertain exactly what the contents of 
each material by that method are. (:Unfortunately the 
exact method's full description has been lost in transit:) 
It would seem therefore that in those countries which, 
like Germany and Belgium, pay great attention to the 
promotion of agriculture, the chemists who exercise any 
control over the manufactured articles are careful in avoid- 
ing what might be understood as a measure unfair to the 
manufacturer's interests. In all cases the minutiae even of 
the method are known to the manufacturers so that they un- 
hesitatingly submit to control on part of the experiment 
station. In this country, however, matters have not yet 
arrived at this satisfactory point, though several attempts 
have been made to bring about uniformity of method. 
There is not even uniformity in the preparation of 
samples, much less a careful adherence to one and the; 

*See page 14. 



18 

same method of analysis. If the efforts made up to this 
time by State chemists and other leading agricultural 
chemists are reviewed, it will he seen that the chemists 
themselves admit that the present unsettled state of affairs 
in the analysis question is far from meting out justice to 
the trade. 

For the sake of giving full information to all interested 
in this subject the minutes of the various meetings of chem- 
ists are here reprinted without any abbreviations. 



CONVENTION 

OF 

AGRICULTURAL CHEMISTS 

AT WASHINGTON, D. C. 



The following circulars will explain in brief the object 
of the Convention : 

DEPAETMENT OF AGRICULTURE, 

Atlanta, Georgia, May 20th, 1880. 
Dear Sir : 

The experience of the last fertilizer season has suggested 
to my mind the importance of securing such uniformity of 
method in determining, by chemical analysis, the percent- 
age of valuable ingredients in commercial fertilizers, as 
will give more uniform, and hence more satisfactory results. 
This is especially desirable in determining reverted phos- 
phoric acid. 

"With a view to accomplish so desirable an object, as well 
as others which maybe deemed proper, I have the h^nor to 
suggest the calling of a Convention of the several Commis- 
sioners of Agriculture, representatives from State Boards 
of Agriculture, State Chemists, and Professors of Chemis- 
try in State Universities, and State Agricultural Colleges, 
in those States using large amounts of commercial fertil- 
izers, to meet at some convenient point early in the month 
•of July next. 



19 

I would be glad to have your views on the subject ; and 
if favorable to the suggestion, please nominate some gentle- 
man, who, by general assent, may be informally authorized 
to fix the time and place of such Convention, and issue the 
necessary notices. 

You are also requested to give me the names and post- 
offices of gentlemen in your State, holding either of the 
positions above indicated, which do not appear in the list 
below, that copies of this circular may be sent to them. 

An early reply is desirable. 

Yery respectfully, 

J. T. HENDERSON, 

Commissioner of Agriculture. 



DEPARTMENT OF AGRICULTURE. 

Atlanta, Georgia, July, 1, 1880. 

Dear Sir : I am gratified to announce that the recent cir- 
cular letter which 1 had the honor to issue, suggesting the 
calling of a Convention for the purpose of adopting a uni- 
form system for the analysis of commercial fertilizers, has 
met with favorable responses from a large majority of the 
gentlemen to whom it was sent. A like majority has im- 
posed upon me the duty of fixing the time and place of said 
Convention, and issuing the necessary notices for the same. 
After correspondence with others, and due consideration of 
the interests involved, I have decided upon Wednesday, the 
28th ot July, as the time, and Washington, D. C, as the 
place, for the assembling of the proposed Convention. You 
are accordingly, respectfully and earnestly invited to be 
present and participate in the Convention. 

Every reasonable facility for the deliberations of the Con- 
vention will be afforded by Hon. Wm. G. LeDuc, Commis- 
sioner of Agriculture, who is in hearty sympathy with the 
object sought to be accomplished. I have appended hereto 
a list of names of gentlemen to whom this circular will be 
•sent. 



20 

Trusting that you will find it convenient to attend and? 
give the Convention the benefit of your experience, and 
requesting that you will at once inform me ~by letter whether- 
you will attend, I am respectfull} 7 , 

J. T. HENDERSON, 

Commissioner of Agriculture.. 



PROCEEDINGS 



Library Hall, July, 28, 1880.. 

In response to these circulars there assembled — in one of 
the spacious halls of the Department of Agriculture, which 
was kindly set apart by the Commissioner of Agriculture — 
the following gentlemen : 

Prof. R. M. Ballentine, United States Department of 
Agriculture. 

Dr. C. Elton Buck, Analytical Chemist, Wilmington,. 
Delaware. 

Hon. A. P. Butler, Commissioner of Agriculture, State- 
of South Carolina. 

Dr. Peter Collier, Chemist of the United States Depart- 
ment of Agriculture. 

Dr. M. G. Ellzey, Prof. Virginia Agricultural and Me- 
chanical College. 

Dr. C. A. Goessman, Agricultural College, Amherst, 
Mass. 

Prof. W. M. Habirshaw, Analvtical Chemist, New York 
City. 

Hon. J. T. Henderson, Commissioner of Agriculture, 
State of Georgia. 

Dr. E. H. Jenkins, Connecticut Agricultural Experiment 
Station. 

Dr. A. R. Ledoux, North Carolina Agricultural Experi- 
ment Station. 

Dr. G. A. Liebig, Analytical and Manufacturing Chemist,. 
Baltimore, Md. 

Prof. Arthur T. Neale, New Jersey State Experiment*.. 
Station. 



21 

Dr. N". A. Pratt, State Chemist, Georgia. 

R. W. L. Rasin, Manufacturer, Baltimore, Md. 

Dr. Charles U. Shepard, Jr., Chemist, State of South 
Carolina. 

Dr. W. Simon, Analytical Chemist, Baltimore, Md. 

Dr. C. C. Wellington, United States Department of 
Agriculture. 

Dr. H. C. White, Prof. University of Georgia. 

Dr. P. B. Wilson, Analytical Chemist, Baltimore, Md. 

Dr. Theo. R. Wolf, Prof, and State Chemist, Delaware. 

The Convention was called to order at 3:30 P. M., by 
Dr. C. U. Shepard, Jr., who nominated Hon. J. T. Hender- 
son for President of the Convention, reminding the gentle- 
men that it was owing to Judge Henderson's earnest efforts 
that they were brought together. Judge Henderson, being 
called to the chair, after thanking the Convention for the 
honor done him, stated the object of the meeting as sub- 
stantially set forth in the circulars above given. 

Dr. A. R. Ledoux was then elected Secretary of the 
meeting. 

Dr. M. G. Ellzey addressed the Convention, saying that 
Jie heartily endorsed the effort which Judge Henderson was 
making to secure uniformity in the analysis of commercial 
fertilizers. He recognized the need of some general under- 
standing in the matter, and hoped that the discussions 
would take no limited range, but deal with more than one 
-of the questions which have been the cause of difficulty be- 
tween producers and farmers throughout the country. 

Letters were read from Prof. S. W. Johnson, of INew Ha- 
ven, and others, heartily endorsing the object of the meeting, 
and thanking Judge Henderson for his action in calling the 
same. 

On motion of Dr. Ellzey the chair appointed a committee 
on a programme, or order of business, to recommend to the 
Convention what topics should be discussed. The follow- 
ing committee was appointed : Drs. Goessman, Buck and 
White. The committee recommended the following pro- 
gramme. The report was received and adopted. 



22 
PROGRAMME. 

1. Preparation of the roll of the Convention, and decision 
of the right of parties present to participate in the discus- 
sion of various topics, and to vote upon the final judgment 
of the same. 

2. Discussion of the method of estimating soluble phos- 
phoric acid. 

3. Discussion of the method of estimating "reverted" - 
phosphoric acid. 

4. Estimation of insoluble phosphoric acid. 

5. Estimation of nitrogen. 

6. Estimation of potash. 

The Committee consider the above the main topics which 
should receive the consideration of the Convention. Other 
points proper for discussion, should time allow, are, per- 
haps, as follows : 

7. Methods of arriving at commercial valuations. 

8. Agricultural and commercial valuation of " reverted "" 
phosphoric acid. 

In accordance with section 1 of the Order of Business, 
the Secretary was ordered to make out and read the roll of 
the Convention, together with the occupations and profes- 
sions of the gentlemen present. 

Dr. "White moved that only those wh-o are practicing, 
analytical chemists, be considered entitled to vote on the- 
final judgment of the meeting. 

Dr. Ellzey opposed the motion, saying he would very 
much regret to see the Convention limited in that way. 

The Secretary called attention to the fact that all the- 
gentlemen present, but three,* were practicing, analytical 
chemits, and entitled to vote under the above resolution. 

After some further discussion, the resolution was adopted. 

The Convention then, on motion, took up the discussion 
of the 2nd section of the programme — determination of 
soluble phosphoric acid. 

Drs. Goessmann and Ellzey gave their opinions as to the- 
extent and direction which the discussion should have. 

*Messrs. J. T. Henderson, A. P. Butler and R. W. L. Easin. 



23 

It was moved by Dr. Ledoux that a committee of three 
be appointed by the chair to propose to the Convention a 
method for the determination of soluble phosphoric acid. 

Dr. Collier moved to amend, by substituting "five" for 
"three." 

Dr. Shepard moved, as a substitute, that the entire ques- 
tion of the determination of phosphoric acid, in all its 
forms, be referred to a committee of five. 

After discussion, the following resolution was adopted. 

"Resolved, That a committee of five be appointed by the 
chair to consider sections 2, 3 and 4: of the Order of Busi- 
ness, and report thereon." 

The following gentlemen were appointed by the chair: 
Drs. Shepard, Goessmann, Liebig, Jenkins and Wolf. 

On motion of Dr. White, it was ordered that a committee 
of five be appointed to take into consideration sections 5 
and 6 of the Order of Business, and report thereon. Drs. 
Habirshaw, Wilson, Neale, Buck and Pratt were appointed. 

On motion, section 5 of the Order 'of Business was 
amended so as to include nitrates. 

The Convention then took a recess until 6:30 P. M., to 
allow the committee time to report. 



The Convention came to order at 7 P. M. The com- 
mittee on sections 2, 3 and 4 (Phosphoric Acid) offered the 
following report, which, after reading and being discussed 
by several gentlemen at considerable length, was received 
and adopted. 

KEPORT. 

It is recommended by your committee to whom was 
referred the selection of a method for the determination of 
Phosphoric Acid in commercial manures : 

That this convention shall agree to adopt, provisionally, 
the methods recommended by Fresenius, Neubauer and 



24 

Luck in their article " On the best methods for the analysis 
of artificial manures." 

Zeitschrift for Analytische Chemie, X pg. 133 with the 
following suggestions : 

1. That the flask containing the residue (after the extrac- 
tion of the Soluble Phosphoric Acid) and the solution of 
citrate be introduced into a cold water bath, whose temper- 
ature shall be rapidly raised to 40 degrees C, and there 
maintained for one-half hour, the flask being shaken every 
five minutes. 

2. That the determination of the "Reduced" Phosphoric 
Acid be indirect. 

3. That all the determinations be gravimetric. 

4. That a committee of two — to be named by the chair- 
man — be appointed to prepare, on the above basis, a detail- 
ed method for the analysis of commercial manures, and to 
distribute the same among the members of this Convention 
and others interested by this action. 

CHARLES U. SHEPARD, Jr. 

Chairman of Committee. 

The following report of the committee on sections 5 and 
6 of the programme (Nitrogen and Potash) was received 
and adopted. 

REPORT. 

Of Committee on Estimation of Nitrogen and Potash in 
Commercial Manures : 
I. Determination of nitrogen (total): 

(a.) When the three (3) forms of nitrogen are present 
(nitrates, ammonia salts, and organic nitrogen), a 
combustion with oxide of copper or plumbic chro- 
mate. 
(b.) When nitrates are not present, a combustion with 
soda-lime and the resulting ammonia estimated with 
Platinum chloride or titrated with a normal solution 
(alkali). 



25 

II. Determination of nitric acid when in presence of am- 

monia salts and organic nitrogen : 

(a.) Nitrates and ammonia salts are brought into water 
solution and the nitric acid is converted into ammo- 
nia by Harcourt & Siewert's process. — Fres. Zeits., 
1871, 334; Jour. Chem. Soc, 1862, 381; An. Chem. 
und Phar., 125, 293 ; Sutton Volumetric Analysis, 
London, 3d Ed., 1S76, 102 et seq.) 

(b.) Nitrates are brought into water solution and the 
nitric acid estimated by Schlossing's method, modified 
by Schultz, vi2;., distillation in presence of Ferrous 
chloride with excess of hydro-chloric acid. The NO 
gas is collected and measured. — (Schlossing's Original 
Paper, Annal. de Chim., 3 ser. torn. 40 479 ; Jourfur 
Pract. Chemi., 62-142.) 

III. Determination of nitrogen existing as ammonia salts: 

The solution in water is distilled with magnesium 
oxide and the ammonia estimated either by the Pla- 
tinum method, or by titration with normal acid. 

IY. Determination of the nitrogen when existing in a 
substance, in separate forms, as nitrates, ammonia 
salts and organic nitrogen : 

(a.) Estimation of total nitrogen by I. a. 

(b.) do nitric acid by Il-b or Il-a). 

(c.) do ammonia salts, III. 

(d.) do organic nitrogen by difference. 

"V. Estimation of potash : 

Only salts of potash soluble in water are considered in 
this report (except when the potash occurs in seeds, 
in which case previous calcination is recommended.) 
(a) Solution in water, removal of sulphates, phosphates 
and magnesia by Barium hydrate, clearing with oxo- 
late and carb. ammonia and precipitating with Plati- 
■num chloride. 

W. M. HABIRSHAW, 

Chairman. 



26 

On motion, it was ordered that the two reports be referred* 
to a committee of two, who should copy them, giving details- 
of the methods to be employed, and to send to each mem- 
ber of the Convention a copy of the same. 

On motion, a letter of Dr. S. A. Goodale wa3 considered 
and referred to the above committee. 

After remarks and discussion of the above reports, it was 
suggested that, since so many agricultural chemists were 
present, it would be desirable to effect a permanent organi- 
zation, to meet from time to time and discuss topics of in- 
terest to the profession. Dr. Goessman offered the following 
resolution : 

"Kesolved, That this Convention form a section in the 
subdivision of Chemistry in the American Association for 
the Advancement of Science, and that their next meeting 
be held in Boston, during the regular meeting of the 
aforesaid Association." 

On motion, Dr Goessman's resolution was adopted. Dr.. 
Shepard thought it would be well to refer the matter to a 
committee to draw up a plan for the permanent organiza- 
tion, and offered a resolution to that effect. Drs. Goessman 
and Wilson were appointed to arrange for a permanent or- 
ganization of the Convention, as called for in the resolution 
of Dr. Shepard. 

On motion, section 7 of the order of business was taken 
up by the Convention. A long discussion followed, which; 
was participated in by Drs. Ellzey, Collier, Jenkins, and 
others. No final action was taken upon this section, but it 
will be further considered at the forthcoming meeting of' 
the Convention in Boston. The Committee on Permanent 
Organization made the following report, which was receiv- 
ed and adopted : 

KEPOET. 

The Committee on Permanent Organization propose that 
Dr. Goessman be made Chairman until the next annual 



27 

meeting in connection with the American Association for 
the Advancement of Science, and that Dr. Ledoux be ap- 
pointed Secretary. p. b. WILSON". 

Chairman. 

On motion, the thanks of the Convention were tendered 
Judge Henderson for his courtesy and skill as presiding 
officer. 

On motion, the following resolution was unanimously 
adopted : 

Resolved, That the thanks of this Convention are hereby 
tendered to Gen. Leduc, Commissioner of Agriculture, for 
his courtesy ; and also to Prof. Collier, the Chemist of the 
Department, for his kindness and attention. 

On motion, the Convention adjourned. 

The committee who were appointed to write out the de- 
tails of the methods of determination of Phosphoric Acid 
have forwarded the Secretary the following 

REPORT. 

Method for the Determination of Phosphoric Acid 
in Commercial Manures. 

1. Preparation of the sample. It is not to be ground,, 
but may be broken up by hand, and should be thoroughly 
mixed as rapidly as possible, and transferred to a tightly 
stopped bottle. 

2. Determination of the soluble and "undecomposed" 
phosphoric acid. 

{a) Two grammes of the material, transferred to a suit- 
able vessel, are rubbed up with a small quantity of cold 
water (carefully avoiding any pulverization,) transferred to 
a filter, and there washed with cold water, which is added 
at first in small successive portions, until the washings no 
longer react acid. 

Soluble phosphoric acid is determined in the filtrate. 

(ft) The filter, containing the "Reverted" and "Undecom- 
posed" phosphate is carefully spread on a glass plate. With 



28 

the aid of a wash bottle containing one hundred cubic cen- 
timeters of a perfectly neutral solution of ammonium citrate 
(sp. gr. 1.09), the residue is washed into a lipped porcelain 
mortar. The coarser portions are allowed to settle, and 
the fluid, with the suspended particles, is poured into a small 
flask. The residue remaining in the mortar is rubbed to a 
very fine paste and brought with the remainder of the am- 
monium citrate into the flask, which is then corked. 

This flask is put into a cold water bath, the temperature 
is rapidly raised to 40 deg. C, and there maintained for one- 
half hour, care being taken to shake the flask every five 
minutes. It is then removed and the contents immediately 
Altered. 

The residue is washed two or three times with a mixture 
of equal parts of water and ammonia citrate solution, and 
used for the determination of "Undecomposed" phosphoric 
acid , 

3. The total phosphoric acid is determined in a separate 
portion of 1 — 2 grammes. 

The other details are as given by Fresenius, Neubauer 
and Luck (loc. cit.). 

The committee have read with great interest the commu- 
nication of Dr. S. L. Goodale, referred to them, and beg 
leave to return it to the Secretary for presentation at a fu- 
ture meeting of the Convention, when its contents may re- 
ceive the attention they deserve. 

CHARLES U. SHEPARD, Jr. ) n 

EDW. H. JENKINS, \ Commit t ee - 

The above is respectfully submitted. 

A. R. LEDOUX, 

Secretary. 
J. T. HENDERSON, 

Chairman. 



29 



PROCEEDINGS OF THE SECOND MEETING 

OF THE 

CONTENTION OF AGRICULTURAL CHEMISTS, 

Held at Boston, Mass., Aug. 27, 1880. 



The meeting took place in the Library of the Society of 
Natural History, which was kindly set apart for the use of 
the Convention. The Convention came to order at half- 
past two. Dr. C. A. Goessman occupied the chair. About 
twenty-five gentlemen were present. 

The minutes of the meeting in Washington were read 
and approved. 

Drs. Caldwell, Kerr, "White, Atwater. Sharpies and Le- 
doux, took part in discussions as to the advantage of per- 
manent organization, the choosing of a name, etc., etc. A 
general opinion prevailed that, for the present at least, it 
would be sufficient to form a sub-section or sub-division of 
a sub-section of the American Association for the Advance- 
ment of Science. It was suggested by Dr. Clarke, of Cin- 
cinnati, that we unite with botanists, practical agricultur- 
ists and others, to form a sub-section of agricultural scien- 
tists, instead of simply organizing as agricultural chemists. 
This proposition did not meet with general approval. It 
was pointed out that efforts were already being made to 
organize a Club of Scientific Agriculturists; that, in fact, 
such an organization had been effected the preceding day. 
It was also stated that such an organization need not con- 
flict in any way with one devoted especially to chemical 
work relating to and connected with agriculture. 

The minutes of the Washington meeting having been 
approved, the Chairman stated that the next business in 
order was the reading and adoption of the report of the 
committee of two, to whom was referred by the Conven- 
tion (for elaboration and amplification) the reports of the 
committees on the determination of Phosphoric Acid, Am- 



30 

monia and Potash, adopted by the Convention in Washing- 
ton. The reading of the report brought out considerable 
discussion as to the methods which were recommended, in 
which Drs. Atwater, Caldwell and others took part. The 
reports were adopted provisionally for one year. 

Dr. Clarke stated to the Convention that a movement 
had been inaugurated to have a section of chemistry in the 
American Association for the advancement of Science, and 
suggested that this very desirable object could possibly be 
attained more easily by showing the Association that, not 
only were the chemists ready to form such a section, but 
were even ready to form at least one sub-section — of agri- 
cultural chemistry — whenever the way was open. Dr. 
White offered the following resolution : 

"Resolved, That a committee of three be appointed by 
the chair to take such steps as may be necessary for securing 
the formation of a permanent chemical section in the 
American Association for the Advancement of Science, and 
the establishment of a sub-section of agricultural chemistry 
in such permanent section, should it be formed." 

The chairman appointed as committee, Drs. White, Cald- 
well and Ledoux. 

An extended discussion was then had concerning the 
l3est means for securing the co-operation and adoption of 
the best methods of analysis by not only the chemists in 
the Convention, but all those whose duty it was to make 
analysis of commercial fertilizers throughout the country. 
Dr. Sharpies thought methods endorsed by the Convention 
would be considered binding by other chemists throughout 
the country, but considered that experiments should be 
made fully to establish the fitness of the methods proposed 
at the Washington meeting. 

Dr. Ledoux said that while he thought we would still be 
more or less dependent for some years upon the thought 
and experiments of the chemists of the Old World, the time 
had come when we should make more experiments for our- 
selves, even if we do nothing more than confirm the methods 



31 

^and results of Fresenius, Neubauer and Luck, and others. 
He suggested that many chemists would be glad to insti- 
tute any experiments needed to attain the end desired, and 
that the time had come to collate and examine the various 
methods of determining Phosphoric Acid, Ammonia and 
Potash, which have, .from time to time, been published by 
■our agricultural chemists. He considered that the collec- 
tion and examination of the methods published and their 
-adoption and reduction to one system, after careful experi- 
mental research, would give to the final action of this Con- 
vention an authority which would be recognized by every 
•one. Several gentlemen expressed their willingness to 
make any experiments which might be desired, and to do 
"their share in perfecting a scheme of analysis. The follow- 
ing resolution was unanimously adopted : 

"JResolved, That a committee of five be appointed by the 
•chair to secure the co-operation and experimental research 
of agricultural chemists, to collect and examine the various 
^published methods of fertilizer analysis, and to make a 
report at the next meeting of this Convention ; and that we 
individually pledge ourselves to conduct, for this commit- 
tee, any experiments or tests which they may desire." 

The chair appointed Drs. S.W. Johnson, C. U. Shepard, Jr. 
Peter Collier, "W. O. Atwater and (x. C. Caldwell. 

It was moved by Dr. Collier, that when we adjourn, we 
adjourn to meet at the same time and place, in 1881, as the 
American Association for the Advancement of Science. 
-Adopted. 

It was moved and seconded, that the present Chairman 
•and Secretary hold over until the next meeting. Adopted. 

On motion, the Convention adjourned. 

A. E. LEDOUX, 

Secretary. 



32 



PROCEEDINGS OP THE THIRD MEETING 

OF THE 

CONTENTION OF AGRICULTURAL CHEMISTS,, 

Held at Cincinnati, Ohio, Aug. 18, 1881. 



MINUTES. 

The meeting took place in the room in Music Hall, as- 
signed to the Chemical Section of the American Association 
fok the Advancement of Science. Dr. Goessman, the- 
Chairman appointed at the Boston meeting, being absent, 
the Convention was called to order by the Secretary, A. R.. 
Ledoux. 

A large number of chemists were present, among them :. 

W. O. Atwater, Middleton, Conn. 

A. L. Baker, Baltimore, Md. 

B. N. Baker, Baltimore, Md. 

H. Carrington Bolton, Hartford, Conn. 
G. C. Caldwell, Cornell University, N. Y. 
H. Y. Castner, New York City. 
A. F. dwell, Wood's Holl, Mass. 

C. W. Dabney, Jr., State Chemist, N. C. 

E. "W". Davison, Baltimore, Md. 
G. W. Davison, Baltimore, Md. 

F. P. Dunnington, University of Virginia. 
Albert C. Hale, Colorado. 

T. M. Hopke, New York City. 

R. C. Kedzie, University of Michigan. 

A. R. Ledoux, New York City. 

G. W- Lehmann, Baltimore, Md. 
Nat. ~W. Lord, State Chemist, Ohio. 
C. F. S. Lowe, Augusta, Ga. 

"W. Mager, Baltimore, Md. 

J. G. Mattison, New York City. 

Lockwood Myricke, Boston, Mass. 



33 

Paul Schweitzer, University of Missouri. 

W. Simon, Baltimore, Md. 

Eugene A. Smith, University of Alabama. 

J. Lawrence Smith, Louisville, Ky. 

Alfred Springer, Cincinnati, Ohio. 

€. M. Stillwell, New York City. 

W. P. Tonry, Baltimore, Md. 

O. Henry Williams, Baltimore, Md. 

P. B. Wilson, Baltimore, Md. 

C. Gilbert Wheeler, Chicago, 111. 

H. C. White, State Chemist, Ga. 

Letters were read from Drs. Collier, Goessman, Johnson, 
Liebeg, Weil, and others, regretting their inability to attend 
the meeting. 

In opening the meeting, Dr. Ledoux recited, the history 
of the Convention so far, and read extracts from the reports 
of the Washington and Boston meetings, showing what had 
been done. He called attention to the fact that there had 
been comparatively little complaint since the Washington 
meeting, in regard to the results obtained in the determina- 
tion of nitrogen, potash, total and soluble phosphoric acid ; 
but that, in spite of honest endeavor, on the part of chem_ 
ists who attended the foregoing meetings, to adhere strictly 
to the methods laid down and adopted by the Convention, 
the determinations of insoluble or reverted phosphoric acid 
have shown the most unfortunate discrepancies. These 
discrepancies were clearly as great as they had ever been 
before there was any attempt to arrive at uniformity in 
method. He said it had been the experience of manv that 
working on the same sample, in the same laboratory, two 
chemists would get results absurdly at variance, and we 
have, as far as he could see, come no nearer a solution of 
the difficulties than we were two years ago. As a proof of 
this, Dr. Ledoux cited a notable example. Soon after the 
Washington meeting Dr. Shepard very carefully prepared 
five samples of artificial fertilizers, and submitted them to 
a number of chemists specially engaged in agricultural an- 



34 

alysis. Each analysis was made in duplicate or triplicate^ 
following most carefully the methods laid down by the 
Washington Convention, with results simply ludicrous, as- 
far as insoluble phosphoric acid was concerned. These 
analyses were never published, but being privately circula- 
ted among some of the chemists who attended the Washing- 
ton Convention, tended to prove what many had found out 
in the meantime by their own experience, that not yet had 
a method been reached, which, in different hands, would 
give even approximately uniform results. Dr. Ledoux 
further stated that another difficulty presented itself in the 
fact that we have, yielding more or less to our citrate sol- 
vent, not only truly "reverted" phosphoric acid, but insolu- 
ble phosphoric acid too, in certain mechanical forms ; such 
as in the Peruvian, Orchilla, Curacoa, Bat, and other guanos. 
Dr. Ledoux further stated what were the rules as to 
voting, etc., and the programme for business adopted by the 
Convention at Washington, and said that these were adher- 
ed to in the adjourned meeting in Boston. 

Dr. P. G. Caldwell was then called to the chair. 
The minutes of the Boston meeting were read and ap- 
proved. 

The reports of committees being called for, Dr. White,, 
Chairman of the Committee on Permanent Organization, 
reported that their efforts to establish a permanent section 
of chemistry in the American Association foe the Ad- 
vancement of Science were about to be successful, and 
that said section would probably be organized on the 19th. 
After the organization of said section the way would be 
opened for the organization of a sub-section of agricultural 
chemists. The report was accepted. 

Prof. Johnson, Chairman of the Committee of Pive "to 
secure the co operation and research of agricultural chem- 
ists on the present methods of fertilizer analyses," not being 
present and having forwarded no report, and Drs. Caldwell 
and Atwater being members of said committee, they were 
called upon by the Chair for information. They reported 
that one or two communications had been forwarded to 



35 

them by the Chairman; but it was their opinion that no 
definite conclusions had been arrived at by the Committee. 

It was moved and seconded that the rule for voting adop- 
ted at the "Washington Convention and adhered to in Boston 
should also govern the present Convention. This rule is as 
follows : "Only those who are practising, analytical chem- 
ists shall be entitled to vote on the final judgment of this 
meeting." Drs. Dabney, Schweitzer and others, then 
opened the discussion in regard to the present methods in 
use for the determination of insoluble or reverted phos- 
phoric acid, calling attention to the dissatisfaction which 
existed with the present , methods, and also showing the 
difficulties in the way of arriving at any method which 
would be universally accepted. 

Dr. J. Lawrence Smith said that although he had not 
recently made any especial investigations with fertilizers,, 
he had for years made a study of soils ; and he stated that 
the value of a phosphatic material depended as much on the 
soil as it did on the chemical condition of the phosphate. 
He considered that there was no such thing as an absolutely 
insoluble phosphate, from an agricultural point of view, 
and that after the mechanical condition of the phosphate 
had been taken into consideration, he did not know why 
some simple method of testing the relative solubility could 
not be arrived at by agreement. For example, why could 
we not use a given solution of dilute hydrochloric acid, on a 
given weight of phosphate, allowing it to act for a given time, 
at a given temperature ; or some other equally simple plan. 

Mr. R. W. L. Easin, President of the Chemical and 
Fertilizer Exchange of Baltimore, then presented the follow- 
ing petition : 

Chemical and Fertilizer Exchange, 
Eialto Building, Second Street, 

Baltimore, Aug. 18 th, 1881- 
To the Association of Agricultural Chemists : 

Gentlemen : The Chemical and Fertilizer Exchange of 
Baltimore City, of which I have the honor to be President,. 



36 

and the views of which, on the question of analysis, I re- 
spectfully beg to lay before you, is an organization formed 
for the advancement of the commercial character of this 
line of trade, and hence actively engaged in watching the 
closely allied interests of the guano industry, of agriculture ? 
and of agricultural chemistry. 

Iu submitting the following report I beg leave to state 
that the Exchange, in giving expression to the opinion 
hereinafter contained, has been guided by the experience of 
all its members. The grave importance of the decision at 
which this convention will arrive, will, I trust, be readily 
conceded, and the Exchange, it gives me pleasure to an- 
nounce, entertains the firm belief that you will give its 
views the consideration to. which the practical experience of 
its members — the manufacturers — appears to be entitled. 

The method for the determination of reverted or precipi- 
tated phosphoric acid in fertilizers, adopted provisionally at 
the Convention of this Association, at Washington, in July, 
18S0, has now been in practical operation for over two 
years, and has therefore undergone a thorough trial, and the 
result has been by no means satisfactory. The experience 
of the chemists corroborates the experience of the manufac- 
turer. The Exchange openly avows that the continuance 
of the citrate method, under the rules adopted at "Washing- 
ton, would be the cause of great dissatisfaction. Yet, in 
urging upon you the adoption of the oxalate process with 
•specified rules, in lieu of the citrate method, the Exchange 
urges this change only and solely for the reason that, in 
their opinion, only the oxalate method metes out equal jus. 
tice to manufacturer and farmer. The subjoined analyses 
will forcibly illustrate how the citrate method, under the 
Washington, rules, does crying injustice to the guano trade 
and to the farmer. For example, a sample of acid phos- 
phate analyzed by that process, allowing thirty minutes as 
time of digestion, at a temperature of 40° C, using 50 0.0. 
to 1 gram., gave : 



37 

2.75 j Soluble I 7 . 29 Avail . Phos . Acid . 
4.54$ Keverted ) 

while the same sample, allowing sixty minutes for digestion 
at 90° C, applying 100 C. C, to 1 gram, showed : 

2.62 Soluble V A ^ phos ^ 

10.71 Keverted ) 

This demonstrates clearly that the citrate method, under 
the rules adopted at Washington, in July, 1879, fails, to 
show the total amount of available phosphoric acid contain- 
ed in the sample in question. For, if it were not contained 
therein, then the second analysis could not make it appear, 
and hence the reality of the existence of 13.33 per cent, as 
against 7.29 per cent., as shown by adherence to the Wash- 
ington rules, is indisputable. Now the manufacturer, as 
well as the farmer, is entitled to know the true character of 
the goods offered for sale or bought; the former, because 
the analysis determines the commercial value of his goods ; 
the latter, because it is his interest to know what he is ac- 
tually applying to the soil for its amelioration. 

But, in all States where analyses are required and made 
by the respective Departments of Agriculture under the 
Washington rules, the manufacturer is given credit for 
much less than his goods are intrinsically worth, and the 
article is deteriorated in the eyes of the purchaser. The 
former, on the other hand, is led to believe that he is buying 
an inferior article, when, in point of fact, the actual ingre- 
dients far exceed his expectations. 

A similar experiment with ammoniated goods gave the 
following results : 

Sol. Phos. Acid 3.59 ) Total Avajl 11/r5 
Eeverted Phos. Acid 8.16 f 

under 60 minutes digestion, 90° C. and 100 C.C. to 1 grm. ; 

while a strict observance of the Washington rules gave only- 
Sol. Phos. Acid 3.59 ) Total AvaiLj 913i 
Eeverted Phos. Acid 5.15 ) 



38 

The latter analysis would thus debar from sale this ferti- 
lizer in all States where a minimum standard of 10 per cent, 
is required. 

How unjust it is to give the manufactured goods the 
character of an inferior article when they do not deserve it, 
how unjust to keep from the farmer the correct information 
as to what he is buying, need not be dwelt upon here. 
Suffice it to say, that the adoption of a uniform process, 
which assigns to each article its true intrinsic value, is an 
imperative demand recognized by all chemists. Nor is this 
all. The citrate process, under the Washington rule, has 
been the cause of much fault-finding with chemists, when, 
in point of fact, the scrupulously conscientious adherence to 
the above rules was all chemists could be blamed for. Yet 
they have been not unfrequently blamed for incorrectness 
when they sent analyses to manufacturers, which showed 
considerable less percentage of the various ingredients than 
the manufacturer full well knew must be — as a matter of 
fact, was contained in the goods analyzed from the formula, 
and proportion in which the ingredients were put in. Thus 
the method which has been provisionally adopted two years 
ago, has failed in every respect to be more than a fruitful 
source of complaint and friction. 

It appears, therefore, not only expedient, but absolutely 
necessary to have a uniform method adopted which will fix 
the commercial value of fertilizers according to their intrinsic 
value, and assign also proper value to all phosphatic sources- 
Science must render a service to agriculture by giving the 
farmer correct, reliable information as to what he is buy- 
ing, and another service to the fertilizer trade by giving 
their goods the credit they deserve. As is well known, of 
all constituents of a fertilizer, the most important factor is 
the available phosphoric acid ( whether derived from 
phosphate of lime or phosphate of iron ), and the larger 
percentage of this is mostly furnished in the reverted or 
precipitated phosphoric acid. 

The oxalate process, which this Exchange respectfully 
urges upon this Convention for favorable consideration, has, 



39 

so far as known to the members of the Exchange, been giv- 
ing general satisfaction, and has, moreover, been used by 
many chemists in preference to the citrate method on ac- 
count of its greater accuracy. It appears less liable to 
error, has shown the products of the manufacturing estab- 
lishments to be what the farmer's experience confirmed 
them to be, by the practical results obtained, and seems 
therefore, open to the least objection. 

In confirmation of this opinion, I beg to hand you a 
letter of Dr. G. A. Liebig, and analyses by Drs. Liebig, 
Shepard, Castner, Collier and Ledoux, all of which are re- 
spectfully submitted for your earnest consideration. 

A. De Ghequier, It. W. L. Easust, 

Secretary. President. 

Accompanying the foregoing petition were the following 

papers : 
Laboratory of G. A. Liebig, Ph. D. : 

- Baltimore, Aug. 16, 1881. 
A. De Ghequier, Esq., 

Secretary of Chemical and Fertilizer Exchange, Balto. 

Dear Sir : Your favor of the 27th ult. duly received. 
You ask me to give expression to such reasons as I may 
have for preferring the "oxalate" to the citrate method in 
the determination of precipitated or reverted phosphoric 
acid in commercial manures. 

Upon this subject I think I can hardly say more than I 
have said already in the correspondence which you have in 
your possession, covering replies to interrogations pro- 
pounded by a Committee of your Exchange. Still, as you 
desire further expression, I will, at the risk of repetition 
briefly give a few reasons, which have always been of suf- 
ficient weight with me, as a chemist, to cause me to favor 
the oxalate rather than the citrate method in such deter- 
minations. In this conection it is only proper that I should 
remark that, when the subject was under consideration in 
Washington, I urged my views, which have always been as 



40 

they are now ; but being in the minority, I was content 
with the provisional adoption of the citrate method, feeling 
sure that time would indicate the correctness and justice of 
those views more effectually than my simple protest. 

In the remarks I make, please bear in mind that when I 
refer to either method it is with the understanding that it 
will be carefully and conscientiously followed. You will 
feel the force of this provision when I tell you it is only 
within a week or two that a prominent chemist wrote me 
that he should like to know a method by which all chemists 
could surel} 7 find the same results ; to which I answered 
to the effect that no method would ever insure the correct- 
ness of chemists. 

In the correspondence before named, I had the pleasure 
of telling your committee, that identical, or nearly identical 
results can be reached by either method. The difficulties,, 
however, of doing the work correctly are more numerous 
with the Citrate than with the Oxalate method, and it is- 
laid down that of two given methods the simpler is to be- 
preferred ; which is common sense. 

One serious difficulty, I have found, is in the fact that 
the commercial Ammonium Citrate has a decided acid re- 
action, rendering the utmost caution necessary, so much so 
that it became a habit with me to manufacture it for myself;, 
and this precaution becomes more necessary when we are 
dealing with articles containing ferric and aluminic phos- 
phates. The chemist, not knowing the nature of the article 
sent him for examination, should, of course, prefer a method 
which is incapable of discrimination, which, in my opinion, 
is the case with oxalate, while citrate can discriminate 

It is, of course, idle to pretend at this time, that a phos- 
phate containing iron or alumina, if made available, is not 
as valuable agriculturally and commercially as any other 
phosphate containing an equal amount of so called available 
phosphoric acid. Indeed, it is Mulder who goes so far as to 
attach the greater value to phosphate of iron, and my per- 
sonal experience warrants the assertion that it is equally as. 
valuable as phosphate free from such combination. 



41 

I do not see that I can say anything more than I have- 
already said to your exchange, except that I hope the ap- 
proaching meeting of chemists at Cincinnati — to which I am 
prevented from going — may adopt the method open to the 
least objection, and, as uniformity in results is the thing so 
much desired — in my opinion, the oxalate method should 
be adopted provisionally or permanently, as the experience 
and wisdom of those present may decide. 

Hoping this, in conjunction with my former letters, may/ 
convey my full meaning. 

I am, dear sir, 

vour obedient servant, 

G. A. LIEBIG. 

United States Department of Agriculture, 
Washington, Aug. 5th, 1881 
W. E. Lawton, Esq., 
My dear sir : 
Your letter of the 2d came duly to hand. Please accept 
my thanks for your promptness. Now, as to the method of 
analysis : I can assure you that I am very conservative, and 
by no means inclined to believe without question that the 
method adopted is the best one to determine the value of 
the phosphates analyzed. Of cource, I don't mean their agri- 
cultural value, for you and other dealers can alone fix their 
commercial value. But I am aware that experiments alone 
upon the crop can determine the relative value of these 
different forms of phosphoric acid, and as a chemist, even, I 
could not now say what was the difference between that P2 
O5 soluble in excess of hot citrate of Ammonia, and that 
in cold ; or that soluble in oxalate solution. In fact I do not 
know that there is any difference in its value to the growing 
plant. I assure you that in any arguments you may have 
to advance, you will have in me a listener as free from any 
prejudice as one can be who has been interested in these 
matters for twenty years. I hope that the very best method 
known, or capable of being devised, may be adopted for the 
analyses of these phosphates, and I am wholly with you to. 



42 

that end, and I think no agricultural chemist will be willing 
to oppose such a result being brought about. 
Sincerely yours, 

PETER COLLIEE. 



Massachusetts Agricultural College, 
Chemical Department, 
Amherst, Mass., Aug. 9, 1881. 
W. E. Lawton, Esq., 

President of the JNTavassa Phosphate Co., New York. 
Dear Sir : 

I regret that previous engagements do not permit me, 
during the short period of time left between the arrival of 
your sample of phosphate (Aug. 8th,) and the beginning of 
the Cincinnati meeting, to carry out your request regarding 
their chemical analysis as directed. As the results of the 
desired examination cannot be secured, to answer your pur- 
pose as specified in your letter, as far as time is concerned, 
I shall not begin the work until otherwise informed I ex- 
pect that the Committee appointed by me, as Chairman of 
the Association of Agricultural Chemists at their Boston 
meeting — August 1880 — Professors S. W. Johnson, Cald- 
well, Shepard, Collier and Atwater — to investigate farther 
the various current modes of fertilizer analysis, and to report 
at the coming meeting at Cincinnati — will do much, direct- 
ly and indirectly, to reconcile contending views. One of 
the main objects of our young organization consists in a 
systematic effort to harmonize the interests of the farming 
community and the manufacturers of fertilizers, and thereby 
promote agricultural and industrial progress throughout the 
country. Please accept my thanks for your confidence. 
Yery respectfully yours, 

C. A. GOESSMAN. 

The accompanying analyses were also exhibited by Mr. 
Rasin with the following explanation : 

With a view of showing the relative merits of the Wash- 
ington Citrate, the "high" citrate, and an oxalate method 



43 

•of determining reverted phosphoric acid, three samples were 
very carefully prepared from Navassa guano, as follows: 
■One acid phosphate marked "I," one acid phosphate marked 
"II," and one ammoniated phosphate. These samples were 
sent for analysis to nine different chemists with the request 
that they analyze them by the following methods : 

A — The Washington method in all its detail. 

B — The Washington method with the exception of usiDg 
■one-hundred (100) cubic centimetres of citrate solution for 
one'hour, at a temperature of 90 degrees C. 

C — By using oxalate of ammonia (without any definite 
instructions as to the amount, time, temperature, etc.) 



44 



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46 

Mr. Rasin also handed in letters received from a number 
of chemists expressing their views concerning the Oxalate' 
method : in some instances disapproving, in others express- 
ing their willingness to abide by the decision of the Con- 
vention. Professor Tonry discussed at length the disadvan- 
tage of the Citrate method, especially emphasizing the 
injustice which it did to those fertilizers containing large 
amounts of iron and alumina, and in which the reversion 
had been caused by these basis instead of lime. Recent 
experiments were cited which had been made in England, 
Scotland and Germany, to prove that in many instances,, 
at least, reverted phosphate of iron was as valuable agricul- 
turally and the equivalent of phosphate of lime. 

Dr. Simon called attention to the difficulty of obtaining 
neutral citrate of ammonia, or of maintaining it after it 
had been secured, and to the marked effect which was ex- 
erted by different degrees of alkalinity produced by the 
addition of ammonia for the sake of neutralization. In 
contrast to this, he called attention to the stability of oxo- 
late of ammonia. 

He was followed by Dr. Ledoux, who pledged himself, 
as bethought all chemists present would do, to adopt what- 
ever method the Convention endorsed. He called attention 
to the fact that the Washington and Boston meetings had 
each endorsed the method of Fresenius, Neubauer and Luck,. 
-provisionally for one year, that the year had already expir- 
ed, and consequently there is now no authorized or official 
method, so far as American agricultural chemists are con- 
cerned. He further called attention to the difficulty of 
filtering rapidly when the citrate solution is employed, and 
the consequent discrepancies in point of time which must 
exist where one solution, filtering rapidly, remained in 
contact with the solvent for a much shorter period than in 
the case of another. 

Mr. Stillwell said he had used the citrate method for 
years, and in his hands he finds this method quite satisfac- 
tory. He found no difficulty in filtering all solutions con- 
taining the citrate rapidly, if proper care was used. He 



47 

considered the oxalate and citrate methods, when carried 
on under the same conditions, entirely the equivalents of 
each other in guanos and ordinary superphosphates, except- 
ing when iron and alumina were present. In the latter 
case he had observed great discrepancies. The citrate pro- 
cess seemed to favor superphosphates free from iron and 
alumina, which, in his opinion, was rather unjust, as, in his 
experience, superphosphates containing iron and alumina, 
gave as good results on the field as any others. In his ex- 
perience, two chamists in the same laboratory could use the 
citrate method w T ith proper care, aud have their work agree 
within reasonable limits. The same was true of the oxalate^ 

In view of the fact that he has tried both methods, and 
that there was so much dissatisfaction with the citrate, and 
since he considered them, properly conducted, the equiva- 
lents of each other, excepting in the case of iron and alumina 
phosphates, he had concluded to adopt hereafter the oxalate 
method. 

Professor Lord said he considered that a great part of the 
discrepancies and variations was due, not so much to the 
solvent, but to the differences in carrying out the details. 
He hoped that whatever method was adopted, the details 
would be so clearly and plainly stated that it would be im* 
possible to have any more trouble on this account. He 
objected to the term "reverted" as not implying the whole 
truth about the phosphates dissolved by the citrate or 
oxalate solvent, and suggested tnat chemists adopt the term 

"Phosphoric acid soluble in at deg. 0." (whatever 

solvent and temperature might be adopted). He hoped 
that not only the methods of conducting the analysis would 
be very clearly and definitely agreed upon, but that even 
the apparatus to be used in each case should be specified. 

Dr. Lehmann stated that his home was in Weisbaden, 
that he had studied with Fresenius, and was thoroughly 
familiar with the method of Fresenius, Neubauer, and 
Luck, that he knows it was adopted mainly with a view to 
its application for the analysis of bone products and others 
where little or no iron was present. He too considers the 



48 

•difference in method and time of grinding, stirring, shaking 
and filtering, etc., etc., grave causes of discrepancy. In his 
experience oxalate of ammonia solutions filtered uniformly 
well. 

Dr. Tonry moved that instead of the so-called citrate of 
ammonia method, the Convention do adopt provisionally 
for one year oxalate of ammonia of as a solvent. 

Dr. Ledoux stated that there were three interests involved 
in whatever decision was arrived at by the Convention; the 
interests of manufacturers, the interests of farmers, and the 
professional interests of the chemists. Since it was appa- 
rently impossible, either in this country or in Europe, with our 
present lights, to arrive at thoroughly satisfactory methods, 
rendering it impossible to stand upon entirely scientific 
grounds in the discussion, chemists must consider the 
commercial points at issue between buyers and sellers, and 
observe a strictly neutral and just middle ground. 

Dr. White said that he had analyzed over 350 samples of 
fertilizers last year, and found iittle or no trouble with the 
Washington method. He not only checks his work by 
duplicate analyses, but again and again, when the same 
samples have been returned to him without his knowledge, 
"he has found his previous work corroborated. The new 
analysis agreed with the former. He acknowledged that 
his analyses did not alw r ays agree with those of other chemists. 
He stated that we were in posession of but few results 
making comparison of the Oxalate with the Citrate method, 
bmt he did know that "An especial British Commission, 
after considering the very subject which we are now 
•discussing for over two years, decided that the Oxalate 
process was the very worst of all, in regard to the discrep- 
ancies." Since, as has been stated, we are not all agreed as 
to what shall be included by the term "reverted," he w T as 
earnestly opposed to any change, for the present, from the 
Washington method, but preferred that the whole subject 
be again referred to a committee, with instructions to make 
•certain tests which could be suggested. He further stated 
that we could not base a scientific discussion on the analyses 



49 

•of the samples of Navassa Guano just reported, because we 
know nothing as to how they had been prepared, and their 
number was too i'ew to allow us to generalize trom their 
results. He therefore moved, as a substitute to Professor 
Tonry's resolution, that the subject be again referred to a 
committee to investigate and report ; and that, until said 
•report shall be made, the Washington method be adhered to. 

Dr. Dabney seconded this motion, and he declared that, 
following the Washington method as nearly as possible, 
•except in a few minor details, his results agreed closely, and 
he was entirely satisfied with the present system. He, too, 
had found by experience, 'that in artificially prepared 
Reverted Phosphate of Lime, the Washington method was 
•entirely satisfactory, but did not consider it always so in 
Phosphates containing Iron. 

Professor At water said he was pleased to see a spirit of 
•concession and harmony in the Convention, and earnestly 
desired that all interests involved should be carefully 
considered and harmonized. It being one o'clock, he moved 
•that the Convention adjourn until two. Carried. 

The Convention came together at two o'clock, and 
Professor Tonry insisted that his motion should be put. He 
reiterated his previous statement that, in many legal con- 
troversies in which he has been engaged as expert, the Court 
favored the Oxalate method as used in Baltimore. He simply 
desired to press his resolution that Oxalate of Ammonia be 
adopted, leaving the question of method to be settled in 
•some other manner. He stated that he found the Oxalate 
method best in point of expedition and accuracy. 

Dr. Dabney protested against any change, explained the 
system of obtaining samples in North Carolina, and of 
making analyses. 

By courtesy, Mr. Tonry withdrew his resolution tempora- 
rily, to allow a motion that, in the discussion which should 
follow, each speaker should be limited to five minutes. 
Adopted. 

Dr. J. Lawrence Smith considered it possible that a fair 
way out of the difficulty would be to discard the term 



50 

"reverted" altogether, and simply report the amount of 
Phosphate soluble in a given solution, whether of aeid or 
not, as might be agreed upon. 

Dr. Dabney again spoke, repeating his convictions that 
the Citrate method would give equally correct, if not better 
results, than the Oxalate method. 

Mr. Rasin, on behalf of the manufacturers, stated that 
all manufacturers had been intensely annoyed, and their 
business interests seriously interfered with by the great 
difference in the analyses of their goods, and consequently 
in the great difference in the commercial valuations as 
applied by the various State Departments. While he, as 
President of the Chemical Exchange, had presented a 
petition stating candidly that they favored the Oxalate 
method, he wished to say that all they wanted was justice 
and uniformity, and was willing that the Convention should 
adopt the Oxalate method, or the Citrate method, with 
certain changes ; either would satisfy the manufacturers. 

Drs. Simon, Lehmann, I.edoux and others followed, dis- 
cussing the Oxalate method. The last stated that since the 
European chemists have failed to agree on a definite method, 
examining the question from a chemical standpoint ; since 
they have been discussing the question longer than we in 
this country, he feared we, too, would find it impossible to 
agree on any result. He had found it exceedingly difficult 
to keep the temperature absolutely within the limits pre- 
scribed by Presenilis, Neubauer and Luck, but agreed with 
Mr. Rasin that we must strive for truth and uniformity. 

Dr. Atwater said that the manufacturers had put their 
case fairly and honestly, and had agreed to abide by the 
decision of the chemists. It was clear, he thought, that they 
demanded, and rightly, that our method, if not just, should 
be at least uniform. He believed that we should make any 
change which appeared to approach nearer to uniformity 
than we are at present, and he stated that it seemed to him 
that the Oxalate method was a shade nearer uniformity than 
the Citrate. 



53 

Professor Dunnington examined in detail the reports of 
analyses of JSfavassa Guano, which had been submitted to 
the Convention, and pointed out the fact that, although no 
instruction had been given as to what method should be 
employed in the Oxalate of Ammonia text, and definite 
instructions had been given for each of the Citrate tests, that 
the discrepancies with the Oxalate were considerably less 
than with either of the Citrate methods. 

Messrs. Stillwell, Ledoux and others stated their readiness 
to abide by the decision of the Convention, whatever it 
might be, as did Drs. Dabney, White and others. 

The question being called for, the Chairman decided it 
was on the substitute offered by Dr. White. Dr. White wa& 
requested to put his resolution in writing. It was as- 
follows: 

Resolved, That the method provisionally adopted by the 
Washington meeting be continued for one year, and that 
the matter of the relative merits of the Citrate and Oxalate 
methods be referred to a committee of five, appointed by the 
Chair, to report at a subsequent meeting. 

Dr. Ledoux called attention to the extreme improbability 
of our being able, by any amount of experiment, to arrive 
at a scientifically accurate method, and considered it 
necessary to simply agree upon the solvent and method to 
be employed for the coming year, and all stand by the 
agreement. 

The substitute of Dr. White being put was lost by the 
following vote : 

Aye — At water, Dabney, Lord, White. 

ISTo — Baker, Castner, Crowell, Davison, Lehman, Lowe, 
Mager, Simon, Stillwell, Tonry, Wheeler, Williams, Wilson. 

The following gentlemen were absent or refrained from 
voting : 

B. JN T . Baker, Bolton, Caldwell, Davison, Dunnington, 
Hale, Hopke, Kedzie, Ledoux, JMattison, Myricke, Smith, 
Schweitzer, Springer. 

A number of gentlemen explained theii votes : The 
motion was lost. 



52 

The question then recurred to the original motion of Dr. 
Tonry : that Oxalate of Ammonia be substituted for Citrate 
as a solvent. 

Professor Caldwell spoke upon this motion. He had 
listened to the statements of the various chemists with 
interest. He considered that the protection had been mainly 
for the benefit of the farmers and that it was time the 
rnanufactiirers were protected a little. He was, therefore, 
in favor of trying the Oxalate method for a while. It was 
all a matter of experiment, and if, at the end of the coming 
year, the Oxalate method is found to be unsatisfactory, it 
can be readily changed. 

The resolution of Professor Tonry being put, it was 
adopted by the following vote : 

Aye — Baker, Castner, Crowell, Davison, Dunnington, 
Ledoux, Lehman, Lowe, Mager, Stillwell, Simon, Tonry, 
Williams, Wilson. 

No — Atwater, Dabney, Lord, Wheeler, White. 

Absent or refrained from voting : B. N. Baker, Bolton, 
Caldwell, Davison, Hale, Hopke, Kedzie, Mattison,Myricke, 
Schweitzer, Smith, Springer. 

Dr. Ledoux offered the following resolution, which was 
unanimously adopted : 

Resolved, That a committee of seven be appointed to 
consider the best method, and its details, for the determina- 
tion of Insoluble or reverted phosphoric acid by the use of 
the Oxalate of Ammonia; that this committee be instructed 
to report as soon as possible; and that we pledge ourselves 
to adopt the method chosen by the committee ; that the 
committee be appointed as follows : one by the Chair, three 
by the President of the Chemical and Fertilizer Exchange, 
and three to be the State Chemists in charge of fertilizer 
•control present at the meeting, viz.: Drs. Dabney, Lord and 
White. 

The Chair appointed Prof. W. O. Atwater. The Presi- 
dent of the Chemical Exchange appointed Messrs. Lehmann, 
Simon and Stillwell. 



53 

It was moved that a committee be appointed to continue 
the investigation of the whole subject of the determination 
of insoluble phosphoric acid, comparing the various methods 
now in use and reporting to this convention when prepared 
to do so. 

The Chair appointed Messrs. Ledoux, Goessman, Jenkins, 
Liebig and Stillwell. 

It was moved that the committee appointed last year to 
provide for the absorption of the present convention into 
the American Association for the Advancement of Science, 
as a sub-section of chemistry, be continued with full power 
to act. — Carried. 

It was moved that the committee appointed to fix upon 
the method for determining insoluble or reverted phos- 
phoric acid, by means of oxalate of ammonia, be instructed 
to report to the secretary of this convention, and that he 
shall forward copies of their report to agricultural and other 
chemists throughout the country. 

On motion the convention adjourned, to meet upon call 
of the Chair, provided a meeting was necessary before their 
organization as a sub-section of the American Association 
for the Advancement of Science. 



(After adjournment nearly all the chemists present, who 
were not already members of the American Association for 
the Advacement of Science, joined said Association.) 

A. K. LEDOUX, 

Secretary. 

KEPOKT. 

The following is the report of the committee of seven, 
appointed for the purpose of preparing the details of the 
oxalate method. The accompanying letter is also published, 
as it explains somewhat the action of the committee. 



54 

Grand Rapids, Mich., Aug. 25, 1881. 

Dr. A. R. Ledotjx, 

Sec. Conv. Ag. Chemists, 

17 Cedar St., K Y. 

Du. Sir : — Herewith I send you the minutes of the com- 
mittee appointed to propose a method for determination of 
"reverted" phosphoric acid by ammonium oxalate. 

As Dr. Stillwell, the secretary of the committee, was 
obliged to hurry away from Cincinnati, and was not to 
return directly to New York, and, further, as it seemed to 
him, as well as myself, desirable to submit the draft of the 
report to the other members of the committee for approval? 
I undertook to attend to the latter task and forward the 
report to you. As I left Cincinnati somewhat hurriedly 
also, I have not found convenient opportunity to forward it 
until now. 

As you will see the committee felt that, under the cir- 
cumstances, they could do no more now than propose a 
provisional and' temporary plan, but have taken steps toward 
the proposing of something more nearly adequate to the 
demands of the case. It was, however, the feeling of nearly 
all, I think, that the requisite data will be gotten only after 
considerable research, and that without them it will be im- 
practicable to propose a method that will command, or even 
be entitled to the following of chemists generally. 

Will you please see that Mr. Stillwell has opportunity to 
correct the proof of the report. 

Yours truly, 

W. O. ATWATER, 

Chairman. 

REPORT. 

Cincinnati, Aug. 19, 1881. 
Report of proceedings of the committee appointed by the 
Convention of the Agricultural Chemists, Aug. 18, 1881, to 
prepare directions for the use of ammonium oxalate as a 
solvent in the estimation of reverted phosphoric acid. 



55 

Present — Prof. W. O. Atwater, Chairman, Drs. White, 
Lord, Dabney, Simon, Lehmann, and Stillwell. 

This committee, which has been charged with the duty 
of proposing a method for the estimation of so-called re- 
verted phosphoric acid by the use of ammonium oxalate as 
a solvent, finds itself at the outset seriously embarrassed ; — 
•on the one hand by the lack of exact information as to what 
compounds of phosphoric acid are dissolved by ammonium 
oxalate and under what conditions ; and on the other by 
the facts that so few of the chemists officially connected 
with the work of fertilizer analysis were present at the Con- 
vention, and that all such who were present felt themselves, 
under the circumstances, unable to favor the proposed 
•change. 

In the first place it seems best to the committee to pro- 
pose for temporary use a method which approaches as nearly 
as may be to those which have already been employed by 
•some chemists ; second, to attempt at least some investiga- 
tions in the hope of obtaining more light upon the action 
■of ammonium oxalate ; third, so soon as they shall thus be 
placed in condition to warrant it, to suggest a plan for the 
•coming year as they have been directed to do. 

I. PREPARATION OF THE SAMPLE. 

At least 250 to 300 grammes are to be put through a 
sieve with meshes 3 m. m. square (about one-eighth of an 
inch). All lumps are to be prepared by grinding in a mor- 
tar or by cutting until they will pass through the sieve. 
The whole is well mixed and an average sample bottled for 
analysis. Special care must be taken during this operation 
■of sifting that no drying of the sample take place. 

2. Determination of tne soluble and undecomposed phos- 
phoric acid. 

(a) Two grammes of the material, transferred to a suit- 
able vessel, are rubbed up with a small quantity of cold 
water (carefully avoiding any pulverization), transferred to 
•a filter and there washed with cold water, which is added 



56 

at first in small successive portions until the washings no* 
longer react acid. 

Soluble phosphoric acid is determined in the filtrate. 

(b) The residue upon the filter containing the reverted 
and undecomposed phosphates is carefully washed into a 
lipped porcelain mortar with the aid of a wash-bottle hold- 
ing 100 c. c. of a perfectly neutral solution of pure, crystal- 
ized oxalate of ammonium. Each one hundred cubic centi- 
metres of this solution contains two grammes of the salt. 
The coarser portions are allowed to settle, and the fluid,, 
with the suspended particles, is put into a suitable vesseL 
The residue remaining in the mortar is rubbed to a very 
fine paste and brought, with the remainder of the ammo- 
nium oxalate solution, into the same vessel. 

A water bath containing 400 c. c. of water for each sam- 
ple treated is brought to a boil, the flame is removed, and 
the vessel containing the oxalate solution is immediately 
placed in the boiling water. It is then left in the water 
bath for sixty minutes, being shaken every ten minutes. 
At the end of sixty minutes ths vessel is removed from the 
water bath and the contents immediately filtered. The- 
residue is thoroughly washed with cold water and used for 
the determination of insoluble phosphoric acid. 

The Chairman and Secretary were directed by vote to 
prepare samples, and a schedule for experimental work, and 
to invite the co-operation of chemists for trial analyses of' 
the samples submitted. 

The Committee adjourned subject to call by the Chair- 
man. 

CHAS. M. STILLWELL, 

Secretary.. 



57 



SUPPLEMENT 



To Report of Proceedings of the Cincinnati Convention, 
of Agricultural Chemists. 



New York, September 23d. 

The following letter from Prof.' S. "W. Johnson, has only 
just reached the Secretary, after the foregoing report was 
printed and partially distributed. It failed to arrive in 
time for the Cinainnati Meeting, although mailed before 
the middle of August, owing to misdirection. Owing to 
the great value attached to anything from Dr. Johnson in 
the line of agricultural chemistry, and the regret of our 
Convention at the absence of his report, the Secretary pub- 
lishes the letter in this form, rather than not at all. 

A, E. LEDOUX, 

Secretary. 



New Haven, Ct., August 14th, 1881.. 

Dr. A. R. Ledoux, 

Secretary. 

Dear Sir : 

I must beg you to present to the Association of Agricul- 
tural Chemists my deep regrets at being unable to make 
any satisfactory report on Methods of Analyses of Super- 
phosphates. I accepted the chairmanship of the Committee, 
with appointment to which I was honored at the .Boston 
Meeting, after much hesitation and with many misgivings 
in view of the probability that I could command neither 
time nor strength to discharge the duty satisfactorily.. 



58 

Efforts to effect a meeting of the Committee failed, because 
of the wide distances that separate them. Various in- 
vestigations undertaken in the Laboratory of the Conn. Ag. 
Exp. Station, although yielding instructive and valuable 
results, could not be brought to a satisfactory conclusion, 
being interrupted by the regular and necessary work of the 
Station, and finally mj vacation leisure finds me without 
the strength to digest the material that has accumulated, 
and to report the progress attained in a manner at all com- 
mensurate with the importance of the subject. 

I will state a conclusion that is the result of much ex- 
perience, viz : that the citrate of ammonia method applied 
as directed by Fresenius, Neubauer and Luck may easily 
give reasonably satisfactory results on the low-grade super- 
phosphates usually found in our markets, but that it fails to 
extract the "reverted phosphates" when their quantity is 
considerable. 

Thus from " Curacoa Guano " so-called, containing 30$ 
of phos. acid, 50 C. C. of Ammonia Citrate, as exactly 
neutral as it could be made, in h half hour at 40° C, with 
constant and uniform agitation : 



Extracted, 

from 2 grms. Curacoa 


% P205 

5.6 


•' i " " 

A. 


94 
13-7 
16.6 



21.0 



It is evident, then, that for such phosphates the quantity 
of solvent must be increased. 

In conclusion, I beg to be continued another year on the 
-Committee or preferably to be discharged. 

Yours very truly, 

S. W. JOHNSON", 

Chairman of Committee. 



59 



REPORT 

XDr Analysis Obtained from Samples and Schemes fok 
Experimental Work, Prepared by the Chairman and 
Secretary of the Committee Appointed at Cincin- 
nati, Ohio, Aug. 18, 1881, Consisting of W. O. Atwater, 
Chairman, Mess. White, Lord, Dabney, 
Simon, Lehmann, Stillwell. 



In accordance with the request of the committee a scheme 
was prepared, as follows : 

Schedule for tests of Solvent Action of Ammonium Oxalate 
and Citrate upon Phosphoric Acid in Fertilizers. 

In accordance with the request of the committee ap- 
pointed by the Convention at Cincinnati to propose a method 
for the determination of so called "reverted phosphoric 
acid," the following schedule for a series of investigations 
on the solvent action of ammonium oxalate has been pre- 
pared. The plan for the investigation discussed in the 
meeting of the committee involved determinations of phos- 
phoric acid, soluble, reverted, (by difference), insoluble and 
total, in samples of Navassa and South Carolina superphos- 
phates, the insoluble to be determined by ammonium oxalate 
under different conditions as described below. It was 
proposed rather hurriedly and with the feeling, evidently 
shared by all present, that it was at best only the beginning 
of a survey of a narrow portion of the field. In the present 
schedule, besides the determinations specifically included 
in that plan, a few others are suggested, to-wit : the action 
of ammonium citrate by the Washington method upon the 
same samples, the action of both oxalate and citrate upon 
samples of the raw phosphate from which the samples of 



60 

superphosphates are made and the repetition of at least- 
part of the analyses at a later date or dates to learn the 
effect of the reversion which may proceed with time. 

The work as thus laid out will serve to test, in the sam- 
ples operated upon, the uniformity or disagreement of results 
by the different analyses, the comparative action of oxalate- 
and citrate, the solubility of the crude phosphate in the 
reagents used, and, especially, the effect of the factors named 
below upon the solvent action of the oxalate. 

By "Washington Method" is to be understood the method: 
adopted by the Convention of Agricultural Chemists at 
Washington, July 28, 1880; See pages 23 and 24. 

By "Cincinnati Method" is to be understood the method- 
proposed provisionally and for temporary use by the com- 
mittee appointed for that purpose at the Convention of 
Agricultural Chemists at Cincinnati, August 18, 1881. See 
pages 55 and 56. 

The determinations of Total Soluble and Insoluble Phos- 
phoric acid are practically the same by both the above 
plans, and one of each in each sample will of course suffice.. 

The directions for extracting soluble Phosphoric acid be- 
fore proceeding to determination of insoluble by ammonium 
citrate or oxalate will of course be observed in each case. 

A. Study of Solvent action of Ammonium Oxalate un- 
der varying conditions. 
The factors whose influence it is proposed to investigate are :: 

I. Concentration of Ammonium Oxalate Solution. 

II. Patio of Yolume of Solution to Weight of Substance- 
III. Time of Digestion. 
IT. Temperature of Digestion. 

By the "Cincinnati Method" these are : 

I. 2 grms. Ammonium Oxalate Crystals in 100 c. c. of' 
Solution. 

II. 100 c. c. Solution to 2 grms. Substance. 
III. 60 Minutes, 

IT. Initial 100° centigrade, gradually cooled down. 



61 



It is proposed to test each of the above factors separately, 
•and by three determinations, to-wit : 

One in accordance with the Cincinnati Method, which 
may be for convenience be designated as "normal," b. 

One with higher concentration or higher ratio of solution 
to substance or higher temperature or longer time of di- 
gestion, a. 
One with lower concentration, etc., or shorter time, c. 

That is, there will be for each factor, one determination, 
6, in which all conditions will be "normal," and two others 
in which the condition in question will be varied. The 
normal determination will ot course also suffice for the de- 
termination of "insoluble phosphoric acid" by the Cincin- 
nati Method, in the comparison between that and the "Wash- 
ington Method. 

The Details for each factor will be as follows : 

I. Concentration of Solution. 
Three solutions of Ammonium Oxalate will be required. 
a. 4 grms. crystals in 100 c. c. solution 



The three determinations of insoluble phosphoric acid in 
■each sample will involve : 



Weight 

of 

Substance 



Weight of 

am. oxalate 

crystal. 



Volume 

of 
Solution 



Time 

of 

Digestion 



Temperature 

of 

Digestion. 



2 grms. 
2 grms. 
2 grms. 



4 grms. 
2 grms. 
i grms. 



ioo c.c. 
ioo c.c. 
ioo c.c. 



6o minut's 
6o minut's 
6o minut's 



Initial ioo° C. eld dwn 
Initial ioo° C. eld dwn 
Initial ioo° C, eld dwn 



II. Ratio of Solution to Substance. 
Solution as prescribed in Cincinnati Method: for a, 200 
c.c; h, 100 c.c; c, 50 c.c. Details as follows : 



Weight of 
Substance. 



Volume of 
Solution. 



Time of 
Digestion. 



Temperature of 
Digestion. 



2 grms. 
2 grms. 
2 grms. 



200 c.c. 

ioo c.c. 

50 c.c. 



60 minutes. 
60 minutes. 
60 minutes. 



Initial 100° C. eld down. 
Initial ioo° C. eld down. 
Initial ioo C. eld down. 



62 



III. Time of Digestion. 
For a, 120 minutes ; b, 60 minutes; c, 30 minutes. 



Weight of 
Substance. 



Volume of 
Solution. 



Time of 
Digestion. 



Temperature of 
Digestion. 



2 grms. 
2 grms. 



ioo c.c. 
ioo c.c. 
ioo c.c. 



120 minutes. 
6o minutes. 
30 minutes. 



Initial ioo C. eld down. 
Initial ioo° C. eld down. 
Initial ioo° C. eld down. 



IV. Temperature of Digestion. 

For a, 100° 0. continuous ; b, 100° C. initial and gradually 
cooled as by Cincinnati Method ; c, 40° C. continuous. 



Weight of 
Substance. 



Volume of 

Solution. 



Time of 
Digestion. 



Temperature of 
Digestion. 



2 grms. 
2 grms. 
2 grms. 



100 c.c. 
100 c.c. 
100 c.c. 



60 minutes. 
60 minutes. 
60 minutes. 



100° C. continuous. 

Initial 100° C. eld down. 

40 C. continuous. 



B. Comparison of Solvent Action of Ammonium Oxalate 
by Cincinnati Method with that of Ammonium Citrate 
by Washington Method. 

This seems eminently desirable and can be accomplished 
by one more determination of insoluble phosphoric acid in 
each sample. 

The amount of this work which each of the co-operating 
analysts would be able to do, was discussed by the committee 
and it was felt to be of the greatest importance that the 
schedule be arranged and the work divided so as to secure 
the best results with the least labor and in the shortest time. 
If each analyst were to undertake the study of only one of 
the the above factors the united contributions would suffice 
for the immediate purpose nearly as well and at much less, 
cost than if each were to go through the whole. 



6a 

The following schedule will show the amount of work 
required of each analyst on this basis, taking as an example 
the series with the first factor, "I. Concentration of Solu- 
tion of Ammonium Oxalate." 

SCHEDULE OP DETERMINATIONS IN ONE SERIES. 





Raw Phosphates. 


Superphosphates 




Navassa 


S. C. 


Navassa 


S. C. 


Moisture, 


i 


i 


i 


i 


Phosphoric Acid. 










Total, 


i 


i 


i 


i 


Soluble, 






i 


i 


Insoluble in Am. 










oxalate, I. a. 


i 


i 


i 


i 


" " l.b. Cincin. Method 


i 


i 


i 


i 


I.e. 


i 


i 


i 


i 


Reverted, (calculated), " 






(i) 


(i) 


Available, " 


(i) 


(i) 


(i) 


(i) 


Insoluble in Am. citrate, Wash- 










ington Method. 


i 


i 


i 


i 


Reverted, (calculated) " 






00 


(i) 


Available, 


(i) 


(i) 


1 (i) 


(i) 



In two raw Phosphates, In two Super-phosphates. In four Samples. 

Total, 224 

Soluble, 2 2 

Insoluble in am. oxalate, 6 6 12 

Insoluble in am. citrate, 224 

In all, 10 12 22 

/ The above schedule cover the ground specifically agreed 
upon for investigation by the committee. Individuals will 
naturally supplement these at discretion. It would be well 
to investigate other materials as apatite, bone, etc. Repeti- 
tion of the determinations of soluble and insoluble phos- 
phoric acid in the superphosphates at a latter date or dates, 
to be agreed upon, would be very valuable to test the effect 
of the reversion that proceeds or may proceed with time. 
It would also add greatly to the value of the work if analyses 
could be made of the several portions of the superphosphates- 
which are dissolved in water and in oxalate and citrate and 



64 



■which are left undissolved. Researches of this latter sort 
will help materially toward the getting of the fundamental 
-data needed for the construction of just methods of analysis. 

Samples of Raw Navassa, Acidulated Navassa, Raw 
South Carolina, Acidulated South Carolina, were prepared 
and sent by the Secretary to the members of the committee, 
also to the following chemists ; G. A. Liebig, C. U. Shep- 
ard, Jr., S. W. Johnson, G. 1ST. Cook, F. P. Dunnington, 
C. A. Goessman, G. C. Caldwell, H. W. Wiley, T. R. Wolf, 
Peter. Collier, A. R. Ledoux, P. A. Genth, H. Y. Castner, 
W. M. Habirshaw, (in some of the packages sent was in- 
cluded a sample of Curacoa guano.) 

In order to lessen the work to these Chemists outside of 
the Committee, the experimental tests desired were appor- 
tioned as follows, with reference to the four factors of the 
■ scheme. 



Raw & Acid. Navassa. Factor I. & Curacao 



1 



S. Car. 


I. 


Navassa 


" II. 


S. Car. 


" II. 


Navassa 


" III. 


S. Car. 


" III. 


Navassa 


" IV. 


S. Car. 


" IV. 



td 

n 



Rp 



Liebig. 
Johnson. 
Caldwell. 
Shepard. 
Goessman. 
Wiley. 
Wolf. 
Cook. 



"The following table gives the results received by the 
Secretary. The Phosphoric Acid results of Prof. Dunning- 
ton, are obtained by the uranium process, those of Dr. 
Ledoux are the average of two determinations, those of 
•Still well and Gladding by a double precipitation or the 
ammonia magnesic phosphate, checked by a duplicate de- 
termination made by the method adopted at the Convention 
of German Agricultural Chemists held at Halle, in Decem- 
ber, 1881, see pages 11 to 15, the results by the two meth- 
-ods differing- less than 0.10$ 



65 



NAME OF ANALYST. 


IS 


Stillwell 
Gladding. 


T3 

u 

OJ 

a 
a; 
.c 
c/3 


c 


a 
'5 
c 

D 

Q 


y, 





Moisture at ioo° C. 
Raw Navassa, 


3-55 
9-85 
1.30 
6.50 
8-55 






* 5 .I2 

*23.63 
*i.90 

*I2.70 


3.60 

14-55 
i-37 
7.41 
7.92 




Acid 

Raw South Carolina, 


13-93 






Acid " 
Curacao Guano, 


7.17 
7.80 














Total Phosph. Acid. 

Raw Navassa, 

Acid 

Raw South Carolina, 

Acid " 

Curacao Guano, 


28.57 
16.20 
26.58 
18.25 
26.50 


29.81 

15-53 
26.38 
17.91 

28.14 


28.59 
15-69 
26.66 
18.34 


27.42 
14.27 

25-47 
19.69 


30.72 
16.70 
27.64 
20.05 


29.66 
15.84 












Sol. Ph. Acid. 

Acid Navassa, 

Acid South Carolina, 


4-15 
10.45 


4-15 
10.99 


4-38 
10.81 


4.18 
11.82 


4.29 
11.66 


4.46 


Insol. by Cinc. Process. 

Raw Navassa, 
Acid " 

Raw South Carolina, 
Acid " " 


26.64 
5-47 

25-32 
4-35 

I5-3I 


27.81 
5.22 

24-75 
3-73 

26.26 


27.71 

4-33 

25.09 

4.89 


25-74 
4.42 

22.61 
4-65 


28-57 
4-35 

25.29 
4.82 

27.30 


27.72 
4-05 










Insol. by Wash. Process. 




27.61 


24.06 
3-42 

21.89 
4.10 


18.48 
2.80 

19.80 
2.91 






Acid " 












10.12 




Acid " " 










I7-05 


24.82 













*Determined in Air-Bath at 160 — 180 C. 



G6 

Instead of giving the results obtained by each analyst 
from the different subdivisions of the four factors, we give 
below the total averages of the results obtained, selecting 
the two samples of acid, phosphates. 

Acid. Nav. Acid. S. Car. 



Insol. 


by 


Factor I. 


a. 


3-25 


3-34 


" 


" 


" 


I. 


b- 


4.64 


■ 4-49 


<< 


(i 


it 


I. 


c. 


7.12 


4-85 


t i 


t( 


" 


II. 


a. 


4.60 


4-03 


(i 


< i 


" . 


II. 


c. 


5-5i 


5.06 


i i 


" 


" 


III. 


a. 


4.80 


4.11 


" 


a 


" 


III. 


c. 


5.I0 


4.28 


i t 


" 


. ( 


IV. 


a. 


3.80 


4-03 


. ( 


i t 


" 


IV. 


c. 


5.62 


4.S4 



It seems from the above table, taken in connection with 
the separate results given in the reports sent, that the con- 
centration of the solution and the temperature at which the 
digestion is made, are the two most important factors. But 
there is this to be considered — does either the normal cit- 
rate or the oxalate process extract all the so-called reverted 
phosphates, especially those of iron and alumina? If not, 
theD neither will answer and some modification must be 
made. The results of a long series of experiments on this 
point are given in a paper by Mr. Thos. S. Gladding, "on 
the Determination of Reverted Phosphates." Amer. Chem. 
Jour. Yol IY. p. 123. 

We also call attention to the marked difference between 
the results of phosphoric acid, especially in the total as 
given above. Certainly, if such differences are obtained 
in absolutely identical samples, the method for the determi- 
nation of phosphoric acid is not yet fully understood. In 
this connection see papers on the determination of phos- 
phoric acid by F. A. Gooch, Amer. Chem. Jour. Yol. I. p. 
391, and T. S. Gladdings, Jour, of Amer. Chem. Sec. Yol. 
4, p. 135. 

Respectfully submitted to the Committee. 

CHAS. M. STILLWELL, Sec. 



67 

During the spring of 1883 an experiment was made by 
the Committee on agricultural chemistry of the Chemical 
and Fertilizer Exchange. The following method was sent 
with the samples to the chemists mentioned below. 

METHOD. 

Pass the sample through a sieve twelve meshes to the 
inch. 

Put two grams of this into a beaker with about 20 c. c. 
cold water, stir wich a glass rod tipped with rubber, let set- 
tle, filter Supernatant Liquid into a 200 c. c. flask, repeat 
decantation five or six times, transfer residue to the filter 
and continue washing until the 200 c. c. are made up. 

Take 50 c. c. of the above and determine Soluble Phos- 
phoric Acid, (P205)as follows : — precipitate with Molybdic 
Solution, warm to about 50° C, set aside for three hours, 
filter, wash with a mixture of one-half Molybdate Solution 
and one-half water, dissolve in Ammonia Solution, add 10 
c. c. Magnesia Mixture slowly with constant stirring or ro- 
tation of beaker, bring the volume of the liquid up to 100 
c. c. with Ammonia Solution, warm to about 50° C, set 
aside in cool place for three hours, filter and wash. In 
calculating results add .001 grm. Pyrophosphate Magnesia 
for every 50 c. c. Ammonia Solution used in washing. 

Wash the residue from the two grams with the aid of a 
wash bottle containing 100 c. c. Citrate Ammonia Solution 
into a mortar, rub to a fine paste, decant and wash into a 
flask (about 200 c. c. capacity) with the remainder of the 
Citrate Solution. 

Heat a water bath containing 400 c. c. to 65° C, remove 
the flame, place the flask in the bath, let stand half hour, 
shaking every five minutes — the flask must be tightly cork- 
ed — filter, wash with 100 c. c. of a mixture of equal parts 
of water and Citrate Ammonia Solution. Incinerate the 
filter and undecomposed Phosphate, dissolve in Nitric Acid 
and proceed as in determining the Soluble Phosphoric Acid. 



68 

For total Phosphoric Acid, dissolve two grams directly 
in Nitric Acid, make up to 200 c. c. Take 50 c. c. and pro- 
ceed as in determining the Soluble, using 15 c. c. Magnesia 
Mixture. 

Determine Moisture in 5 or 10 grams at 100° C. 

MEMOKANDUM. 

The reagents mentioned in the above method are prepar- 
ed as follows : 

Magnesia Mixture, dissolve 55 grams Magnesium Chlo- 
ride, (fused,) 70 grams Ammonium Chloride in 650 c. c. 
water, and make up to one litre with strong Liquid Ammo- 
ma, (°/ .) 

Ammonia Solution is a mixture of one part strong Liquid 
Ammonia and two parts water. 

Ammonium Citrate Solution is a nentral solution of this 
salt sp. gr. 1.09. One hundred cubic centimeters of this 
solution contains about twenty grams of the Crystallized 
Salt. 

Molybdate Solution, one part Molybdic Acid dissolved 
in four parts Liquid Ammonia, (two parts strong Ammo- 
nia and one part water,) and 'poured into fifteen parts 
Nitric Acid, sp. gr. 1.20. The following will make about 
two litres. 4 oz. Molybdic Acid, 10 \ oz. Strong Liquid 
Ammonia, 5£ oz. Water, when cold pour slowly into 60 oz. 
Nitric Acid, sp. gr. 1.20, (about half C. P. Acid and half 
water,) with constant stirring. 



69 



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W 
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w 

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2 



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o 

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w 



'llOSIABQ - A\ - 3 


icioH vo -^ o 
pi m m pi n O 

tOOsrON covO 




■oipg 

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VB N r^HCO O 

pi o\ p! pi covd 

M MM 




•o;iBg 

'uuBiuqgq •£) -\\ 


PI ^t rONlOCI 
10 0\N ON PI 
PI CT\ m m ^J-io 

M MM 


M CO CO M M CN 

O t~- -3; PI ro vo 

CO VO xj- m' co -j- 

M M 


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co m on o t^ t^ 

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pi cfv pi m -^i-vo 


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d vd -"d- h pi ■4' 


Stillwell 

Gladding, 

N. Y. 

Two 

Independent 

Analysis. 


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M MM 


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t^ O C?N ON M M 

PI On "* co PI VO 

M MM 


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co ^d^d pi d pi 

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Moisture, 

Soluble, 

Reverted, 

Available, 

Insoluble, 

Total, 


Moisture, 

Soluble, 

Reverted, 

Available, 

Insoluble, 

Total, 






'3 'S P3AIOSSIQ 

g^Bqdsoqj ppy 


(bssbabm 7g S 

p9A[OSSIQ) 

a^Bqdsoqa ppy 



70 

The compiler has been unable to ascertain whether at the 
last meeting of the A. A. A. S., held at Minneapolis, any 
action has been taken by the agricultural chemists attend- 
ing it, and if so, what the same has been. It is believed, 
however, that the meeting passed without discussing this 
subject at all. 

Messrs. Stillwell and Gladding, however, have gone over 
the whole ground very carefully and with painstaking 
minuteness and have from time to time published the re- 
sults of their investigations. (:Amer. Chem. Jour. vol. iv? 
No. 2; Chem. News, vol. xlvi, pp. 1831: Amer. Chem. 
Jour. vol. vi, No. 1:) Their work confirms what the trade 
has been aware of all along, namely, that the methods at 
present used in analysing fertilizers do not give accurate, 
uniform and just results. 

As Dr. Atwater stated (see page 50) the manufacturers 
may rightly demand that the method if not just, should be 
at least uniform. It appears also from the views of the 
chemists expressed in the foregoing pages that the reverted 
phosphoric acid whether derived from phosphates of lime 
or phosphates of iron and alumina is a very valuable ele- 
ment of plant food and that the main difficulty exists in 
determining the contents of that ingredient with uniform- 
ity. The discrepancies now existing on that point are so 
great that it seems hardly in conformity with principles of 
justice and equity to base upon results so greatly at vari- 
ance any commercial valuation. Whilst it is true that 
nearly in all States where the agricultural departments 
publish analyses and commercial valuations, they are pre- 
faced by some remarks to the effect that this is only a com- 
parative valuation and does not determine the agricultural 
value of the fertilizer in question, it is also true that the 
farmer may omit to read these brief remarks and even if he 
reads them, he may not fully comprehend the meaning con- 
veyed by them, so that it is fair to presume that he is large- 
ly guided in his purchases by the higher or lower commer- 
cial valuation as given at present. 



71 

Then, again, it is well known that the manufacture!' is 
not consulted in fixing upon the unit-prices used each year 
in each State for the commercial valuations. Phosphoric 
acid, ammonia and potash are said to be worth so and 
so much in one State and a different amount in another 
State and these estimates are understood by the farmer as 
the value of these ingredients to him at the place he pur- 
chases, which is, of course, entirely erroneous. In some 
States the insoluble phos. acid is taken in consideration in 
the computation of commercial valuations, in some it is dis- 
regarded. For instance in Georgia available phos. acid 
(soluble as well as reverted) is valued at 100 per pound, am- 
monia at 200, potash at 60, while in Alabama soluble phos- 
phoric acid is considered worth 120, reverted phos. acid 80, 
insoluble 40, ammonia 180 and potash 50, while the same 
figures in North Carolina are for avail, phos. acid 90, am- 
monia 200, potash 60 ; Ohio adopted 12^0 for avail phos. 
acid, 50 for insoluble phos. acid, 180 for ammonia and 60 for 
potash and in Connecticut a graduated scale applies making 
amonia worth from 260 down to 110, sol. phos. acid 110, 
reverted 80 and insoluble from 60 to 2|0, potash from 70 to 
1J0. From these few instances it is evident that no uni- 
form standard exists and that these prices are more or less 
arbitrary. No doubt those who fix upon these prices do it 
in the belief that these represent fair and just equivalents, 
but after all, the sincerity and honesty of the intention 
affords a poor consolation to the manufacturer who finds 
his goods depreciated in the market. Besides, the prices of 
raw materials are subject to the same fluctuations as those of 
any other commodity and are regulated not only by the laws 
of demand and supply, but other circumstances, and only the 
buyer of raw material at the expiration of each year could 
compute the average price paid by him for each ingredient. 
Even these figures however, would not represent the value 
of the ingredients in the goods for sale, since time (equiva- 
lent to interest), labor and money are being spent by the 
manufacturer in the conversion of raw material into a com- 



mercial fertilizer. Thus the cost of manufacturing is tot 
included, while forming an unavoidable item and the 
farmer generally believes that at his place a pound of phos. 
acid, ammonia and potash represents the stated values for- 
getting that he is so and so many miles from the place at 
which these values perhaps are correct. 

The parental government theory so much detested in this 
country finds in this practice a unique and inconsistent 
application and it would seem as if the German policy of 
letting the manufacturer say what valuations he attaches 
to his goods, is better calculated to insure uniformity. The 
- law of competition necessarily rules out those who quote 
very high figures and the laws of trade by being accorded a 
free play would soon establish certain standard values for 
each season. 

With uniformity in the method of analysis and in the 
carrying out of the same, resonably uniform results would 
obtain everywhere and with standard valuations deter- 
mined upon by the trade, the existing unsatisfactory condi- 
tion of things would soon be replaced by one equally wel- 
come to chemists, departments and manufacturers. And 
these two issues once settled, more uniform and less contra- 
dictory legislative enactments on the subject of the trade 
should not remain beyond the precincts of possibility. Most 
of the grievances are so well recognized by State chemists, 
commissioners of agriculture and other State officials as 
serious obstructions to the development of the fertilizer- 
industry, that it is to be hoped steps looking towards bring- « 
ing about more harmony and accord will be taken and 
result in establishing that which the trade is justly very 
anxious to see established. 



LIBRARY OF CONGRESS 




